So frustrated - nursing

DS is all of the sudden being the worst nurser ever and it is driving me crazy! Normal for him up to about a week ago was nursing sessions of 6 minutes a piece 6 times a day. All of the sudden he has dropped down to 2 to 5 minutes a session and has added a session at night. the 5 minute sessions are the ones at night during the day he never nurses longer than 4 minutes at a time. He has shortened his nursing times before but now sometimes he is not even on long enough to get the let down. I don't understand what is going on. He could be teething (probably molars) but this hasn't happened with his other teeth. He has been on a pooping spree for the last several days. We are up to 2 BLW meals a day (breakfast and lunch) but he is not eating much more than he was with 1 meal.

GRRR, I know I should just go with it but it annoys me that I guess I would like to know why this is hapening and because my boobs hurt! Is this how they drop a feeding or wean themselves? I always offer when he wakes up and before he goes down fot the night and 1 other time in the evening. should I do something differently?

thanks for letting me vent anyway.