Bleeding after sex

Hello y’all, sorry for the tmi. I’ve had the Mirena for about 18 months no problems whatsoever and no period, since I also breastfeed. Today my husband and I were having intimacy and everything was fine. But after around an hr I went to the bathroom and noticed I had bled through my leggings. I freaked out a little since I haven’t bled for so long. But I thought maybe he went too deep and moved the iud? I also haven’t been feeling good the past couple of days so I thought maybe it was my period but the blood was bright red. Not old/brownish looking as to when you haven’t had one for so long. I’ve also been cramping not bad but still. Has anyone experienced this? Any advice?

Ps. I’m thinking of making an appointment just to make sure everything is in placed and looking good. I tried feeling for the strings and can’t seem to find them either 😫I’m so nervous!