Need help I have Diva Cup Questions

So I have a Diva cup size B it feels like it fits good I have no leaks or really any discomfort but I've been using it for two days and sometimes I'll have a small pain feels kinda like a small sharp cramp in My rectal area and some times it hurts a little worse but it seems like it only does it when I have a tampon or a cup in, could this be TSS? Just curious and could this cause health problems? Just wanted to get opinions first