Technical difficulties

Please bear with us. My son is experiencing technical difficulties.

Our son's nickname has been "little buddy" since he was born. It has been a pretty good fit. He is usually a very laid back, easy going kid. Until this week. I realize that children occasionally regress as they're acquiring a new skill, adjusting to a new situation in their life or maybe even a growth spurt. The only event I can see in the near future is his birthday (in 3 weeks) but there have been no other major changes in his life that I know of. However, now that my "little" boy is about to turn 5, he throws a screaming tantrum when I ask him to do things for himself. Now, in the interests of fairness, perhaps I am expecting too much. I have asked him to do such things as: put your PJs in the laundry basket, put your own underwear on and go to the bathroom.

This morning he screamed "I CAN'T DO IT" when I asked him to put his own pants on. I have learned that screaming back will not get the pants on his body. (I am a slow learner but I'm capable of grasping these things eventually). I explained that if he said he could not, he was right. If he tried however, he might be surprised.

Blank look and then more screaming. "I TOLD YOU I CAN'T DO IT!"

I gave up. I picked up the underwear, jeans and half-naked child and put them all in his room.
"You can't run around naked and screaming either," I explained. "I'm shutting the door but you may come out when you are wearing pants."

(He made it out in 30 seconds, dressed.)

Is it the fear of this fifth birthday? He wants me to dress him, undress him, take his coat off, get him a glass a water, wash his hands...

He used to be so proud that he could do all of these himself but I guess the fascination is over. It's hell growing up.