i haven't dealt with your son's situation but did caretake for one year my ex who is paranoid schiz. i found a support group for myself helped me a lot. perhaps you will want to try this...check out your newspaper under support groups.
as for your son, i hope he will follow thru with a psychiatrist. often times medications plus therapy will bring good results. i do hope he is willing to follow thru cause it will greatly improve/decrease his symptoms.
hugs to you. i have two sons and can relate how much you love your son. please try to not beat yourself up. you didn't know why he acted that way until you researched his symptoms. now is the time for the docs to evaluate him for diagnosis. hang in there and please keep us posted. we care.