Pain while using tampons

My son is now 10 weeks. I got my period at 5weeks pp but i still had stitches so i used pads. The next time I got my period I used tampons and everything was okay (I've been getting my period 2x a month 😭). This time it HURTS. My vagina feels sore & sensitive, almost like an itchy sensation? Even if I wear pads it still hurts. Sex is still a bit painful, but I hadnt had any pain using tampons the previous times. Why now? Is it normal? I don't think it's a UTI. Husband and I always shower before hand and I always pee. And it doesn't burn to pee, my vagina is just suddenly so sensitive. 😕