Hi I'm 10+4weeks Pregnant. Yesterday I Had Discomfort That Usually

Hi I'm 10+4weeks pregnant. Yesterday I had discomfort that usually occurs at the time of my periods. Sure enough I heard bleeding and passed something like a clot. Iwas so scared thinking maybe it was my baby. I was immediately taken to ER. During scan they told me baby is fine. But no one knows why I had bleeding. My doctor has suggested strict bed rest and has advised to take susten 200. But once I use it I feel like the entire medicine is coming out and lots and lots of discharge is present along with some dark red clot. I'm very worried and I'm terribly scared to go to the bathroom. Scared of what I may find. Please help clear my doubts. Thank you.