Not sure if this is the right section?

ok so im not too sure if this is the right section to post this in but here goes, and im sorry if this is TMI since being with my partner ( 2 and a half years) really hurts and i mean BAD he doesn't have a bigger girth then anyone else i have slept with but i have NEVER ever experienced pain during , it weird it has only been with him and it hurts ALOT when it first goes in and for about a minute afterwards then its ok and then about 5-10 Min's later it starts hurting again we have tried using lubricants as well but nothing helps i get REALLY swollen afterwards as well to the point where i cant walk because everything feels like its hanging ALOT lower then usual and it feels painful to touch. also when he s inside me afterwards it hurts so badly that im crying, it stings and i cant sit down and the only way to get rid of most of the pain but not all is to go straight into the shower afterwards and stand there for about 15 minutes with the water running onto it...its so weird that this has only ever happened with him and this happens EVERY single time we have that its starting to put me off having . has anyone else experienced this or knows whats going on? please help me i want to find a cure for this but im starting to doubt will be enjoyable all the way through now for the rest of my life. Also this has got slightly worse since pregnancy hense why i didnt know which section to post this in.