K.M.
I agree. I think two is a little young to handle it all, especially for a boy. You are lucky that you have mastered as much as you have already. I would suggest getting some very absorbant training pants to help you through this phase. Imse Vimse makes some great ones that I think would work for you. http://www.cottontailbaby.com/item_40/Imse-Vimse-Training...
What do you use at night? Is he okay through the night and this is a day only thing? I ask as one of my guys struggled a bit during the day (but not at night). Often, he was so absorbed in his activities and playing that he ignored the signals until it was too late. That might be the case with your son. Maybe proactively bringing him to the bathroom and helping him that way might work.
Good luck