Post Partum

Okay ladies need some help. I'm married and had sex at 19 it didn't hurt, kinda felt like I wasn't a virgin even my boyfriend at the time didn't think I was ..... Now when I got married three years ago we waited until our wedding night so it would of been abou 2 years since I had sex. So it felt sore but not painful at all and my husbands Dick is thicker. But now I had a baby 2 months ago and we had sex yesterday after the doctor cleared me. It was sooooo painful. Like it was what I'd imagine my first time to be..... I don't get it at all and I'm confused any other moms have this problem or anyone?