Best Friend

I hooked up for the very first time and it happened to be with my bestfriend (guy) and we are very open about any situation but as of lately I have not wanted to speak to him at all and when he calls or texts me I ignore them or tell him that I will talk to him later because I am busy. Idk what is going on, I don't find the situation awkward or anything it actually quite right when we kissed, it kinda felt like everything fell into place (cheesy sorry) anyway I don't want to see or talk to him at all
Has anyone been through the same thing?
Does anyone know what is going on???