Good night. We've been at it for two months now, and whenever he start…

Good night. We've been at it for two months now, and whenever he starts being fussy, I try to give him a breastfeed, but he doesn't take it and cries hysterically, then he takes it with tears, sucks on it and calms down, sleeps only in my arms for 15 minutes and that's all. Snot is running, I don't think it's teeth. I thought maybe I'm pregnant, took a test and it was negative. I'm worried.