Is my little 5 yr old turning into a schitzophrinic ????

my nearly 5 yr son has started having rages at daycare where as he would punchanother child fer no apparent reason they said no particular child get really angry as smak the kid then go sit down n play like nothings wrong happy again?all in a day he had bitten 2 bubs then punched child.the next day i picked him up from his new kindy class wen i askd how his day went he said ok but i dont want any friends i only need u .i said well if you dont have friends then noone would cum to his birthday i hate birthdays dont want them n proceeded to be grumpy look and broody wen i stopped at shop i made him cum with and he didnt want to then jumped out around and happy as. it appears hes goin from full ragin anger randomly to happy chappy.he just came home from fathers and had clocked his cousin one but again not fighting over a toy or arguing he just felt the need ?? i am worried as he is an absoulote easy going well mannered happy loving child it does not fit and although hes father not diagnosed) is an absoulote nut noone is too high for his verball major anger abuse mouthy as over meanial crap. weather it b police ,judge,airport security ur parents his own ya grandma etc. he will ring me with death threats then not ten minutes later ring back backflip sayin found some good tyres for ya car its bizarre he has been smoking dope since he was ten or so!!i left him finally when sean was 6 mths old as he had a bit of colic he shook him a bit yelling fuck up i called the police that was it.iwas in arefuge for a while wen things settled i would drop sean there for the night apart from not bathing or make him do anything sean loves him and goin there but as it was a ploy to see me the novelty wore off so his stays became 3 weeks apart maybe next time 2 so when he return sean home he wouldnt of made him go to sleep so hed be tired and when dad would go to leave he would be hysterical n every time he screamed dad cum bak in and get agitated n cry n that i tried to explain that 1.you have no regularity so he doesnt know when he will see you again 2. hes sooo overtired and its like a band aid rip it off quick say goodbye keep going and 5 mins later he is fine.it was heartbrkin he got a new lady with kids and started to take him regular .things have been much better for sean although the new lady had a baby left him and left her baby girl with him?? i figured that all he does is abuse and threaten evryone and never follows through with it and sean keeps loving goin there that hes ok .his dad was letting him get away with everything, that he wanted me to be the bad guy which made sean in control of him sean would do the tiniest fake cry and he would pik himup strait away so as he grew he knew who he could play and who he couldnt.so then i also would get the blame for that.these days everything appears to be fine sean wants to go and comes back fine the other thing after the constant abuse of wanting his child i drop him off 9am sat he brings him strait back sunday lunch guarenteed?? i could never understand that cos sean was such an easygoin kid to me u think he would love it and get whatever time he could with him fiday ta sunday arvo ? so this recent behaviour worries me because of his fathers clear madness . we actually have this thing goin with my eldest son n we r constantly singingout i love sean i love u too etc i love will ,ilove you too but with seany i get it 10 times if not more a day with cuddles.befor as soon as hisdad was around he would hate me sorta thing couldnt kiss him goodbye or get a cuddle or nuthin then he would return home not come near me until 5 mins after his dad left back to normal for the rest of the week till next vis now days comes running in mum missed u etc today they rang at 10am and said he wants to come home early. so i dont know if the constant i luv yous and the comment i dont need friends i only need u are worry of losing me or something? but this anger rages and then perfect calm is not right im watching waitin to see if he hurts the animals haha the other thing developing is if he does something for the first time and he cant do it too perfection he gets ansy and refuses to try eg tracing his name because hes wobbly n off line he rubs strait out and says i cant do it and kindy teacher reporting bak same thing wants to be great at it instantly without practise. just incase this means something he also strangely has this little kinda american accent? at first i thought mayb dora but its spanish n nothing like it we dont know any one with acccents and i couldnt pin point any particular show but it doesnt seem to be lessening at all weired huh please tell me what i should do ? do they have shrinks for kids under 5? could this be a passing phase? i have been talking to him on the importance of friends keeping s hands to urself would you like that ect .i ask wats makin u  angry he said corey is a bad kid then said hes my friend?? im so frightend he s schitzo like his father and i wana nip this in the bud before i end up with a crazy kid who turns serial killer or something clearly i will be seeking proper advice just looking for some sort of advice now?