Oversupply

So I was stupidly pumping and breastfeeding thinking it was great to build up my supply in the fridge. Not good. I now have an oversupply and my breasts are always engorged. When I start out breastfeeding, my milk chokes my baby and when he comes off, the milk sprays out like crazy. He's one month old and I am hoping to fix this issue. I also don't know what to do because I have several days where we will be out in public for awhile and I am not comfortable breastfeeding in public. Stressing me out since I need to regulate my supply. Any advice would be helpful!