Blood in Underwear- 16 weeks

Sorry if this is TMI

I went to the bathroom earlier, and I noticed a small drop of blood in my underwear. I couldn't tell how red it was since it looked like it had dried a little bit. When I wipe there was nothing, other than normal discharge. I had a miscarriage a few moths ago, this is is a little worrisome. I have had some sharp in my lower left side but nothing too painful. I am also still nauseous and getting sick a few times a week

I did call my doctor and spoke with the nurse. She didn't seem too worried but said if I see anything else to call back and she will get me an appointment

Has anyone else had this happen?