Painful sex on the depo shot!!

So I got my depo shot back in mid April and didn't start having sex with my husband until 7 days later like I was told to. Only on the 7th or 8th day my vagina got super swollen, itchy, and it hurt to pee. I did what the doc said and kept it clean and dry, slept with no undies on and only wore cotton underwear all of that went away only now after we have sex it's still hurts a little. I've been told it's normal, anyone else think so?