Sore after multiple rounds over the course of a week?

hey so im honestly freaking out a little. My S/O and i have ALOT of sex....like 7-10 rounds a day if we have time....and today when he went to put it in i couldnt handle it and it felt like my insides were melting while we were doing it which caused us to stop....we have been together for months and this has never happened before and both of us are clean and have only been with eachother since we got together....help??