Clear discharge while on period 🤔

Hi ladies😊. So today I'm on my third day of my period & this morning I went to the bathroom I wiped yes there was blood there BUT there were also some clear discharge. I have no idea what it is. I've had it before when I change my tamp. (At night I wear a pad then when I'm about to go run errands I wear a tamp & liner). Also am I the only one who gets a horrible pain in my butthole while on my period?