son changes moods so quickly

How do i know if there is something physical or mental wrong with my son.  He is so loving and nice, and then all of the sudden he gets combative verbally or sometimes some little physical thing.  It just spirals and tells me how much he hates me and can hardly wait to be away from me.  But we get along great the other 80% of the time.  He just has these melt downs every few weeks.  It used to be every couple of months, now it is more frequent.  But I noticed that in the summer when there is no stress he is a lot better.  I have tried to take him to see a psychologist, but he is so stubborn and so strong willed i can not physically get him there.  How do i figure out what is going on with him.  It is disrupting our family so much i need help.

[mammo]

How old is your son?

[Julie359]

Yeah before we can help we need to know how old ur son is, if he is a teenager this sounds very much like a normal situation.... teenagers are famous for their grumpy outbursts, all those hormones issues going on.

[benjimom]

He must be a teenager from what I can understand if she cannot get him physically to places.  

[wendy224]

My son is 13.