Breastfeeding gone hysterical

My son just turned 3 months this weekend. We’ve been breastfeeding since birth with bottles of pumped milk at least once a day or night. However, beginning yesterday, he became hysterical when I tried to feed him. I thought it was gas, nope, diaper, nope. I got a bottle warmed and he was fine. He breastfed okay for the rest of the afternoon but did have another bottle at night with my husband so I could shower and pump and get ready for bed myself. Now, this morning, it happened again. Became hysterical, not as intense because I knew what to try first. He currently is contently drinking a bottle. Could this be a sign that my supply is dropping? Or my letdown is slowing? Teething? First time mom here and it honestly was scary yesterday because he never wails while feeding; practically inconsolable until the bottle. Thanks in advance