Sex after baby

So at my 6 week postpartum check up my doctor told me to wait two more weeks to have sex. So I waited the two weeks and then got my period. So we waited until 9 weeks postpartum to have sex. We used lube but it still hurt really bad. I didn’t bleed but he couldn’t even put it in all the way. Did anyone experience this and does anyone know how long it will hurt for? I’m nervous to have sex again!