I would cut out one of the naps, or at least shorten one of them so he gets more sleep at night.
In the mornings, have some board books or safe age appropriate toys in his crib that he can wake up to and play with for a while. He may hate it at first and throw everything out, but he will get use to them.
I have a 3 year old and a 1 year old as well. For me, I try to nurse when he is calm and wanting it, instead of when he is screaming and demanding it because I am trying to wean him. It is helping so far, try giving your son the meal first or even just a graham cracker to get him to chew on something before nursing.
If you can offer other comfort techniques instead of nursing, like trying to cuddle him and read a book, or blow bubbles, put on music and swing him to it (even fun dance music can snap him out of it), that may help him calm down, or at least redirect his attention and see you as something other than a constant pacifier. He is at the age where he can learn to entertain himself, maybe with blocks or learning toys and puzzles for his age so he can learn independence.
Also, when you go to the bathroom or eat, put him in his room or play yard for a few minutes so he will be safe and you can take a 5 minute break.
Eventually, he will calm down once he figures out how to entertain himself.