Pregnancy feels off

I haven’t gotten my first ultrasound yet (appointment is for the 21) but I am really starting to freak out. I have been showing symptoms but some seem excessive. My stomach is constantly cramping and I am 24/7 nauseous pretty much. According to my last period I’m about 10 weeks and never had any type of bleeding until two days ago when I wiped and in my discharge was brown blood although not a lot. I had no clue I was pregnant and smoked/drank until I found out roughly a month ago. I’m so scared that I am not pregnant/miscarrying or that when I get my ultrasound they are going to tell me that my baby will have something wrong with their health because it took me so long to notice I was pregnant and quit.

I don’t feel like I can talk with the people around me and this pregnancy so far has not gone how I’ve wanted/expected at all and I just keep assuming the worst.