Pain after sex with bf

So my bf is well endowed and we have sex quite frequently. Yesterday when we were have sex my stomach had already been kinda crampy before (this has been a common occurance our whole relationship after sex) but the walls of my vagina were also sore as he was penetrating me. We ending up having to stop bc of that and my lower stomach cramping. Since then and even this morning I’m am still in some discomfort that I ended up taking some Tylenol. I usually finish twice during sex and was just wondering if that on top of him being bigger could cause this or is this normal or what? I don’t know who else to ask and part of me is concerned to if this is a issue and what to do about it.