I am having black, sticky stool?

I know this sounds disgusting, but I'm really looking for advice here, it's not to joke around or be gross. Two weeks ago I started on some new anti-depressant/anxiety medications, that I am now taking with my old anti-depressant. I am on 100 mg of Seroquel, 20 mg of Lexepro, and 150 mg of Trazodone (which I was on before). Three days ago I had thin, black stool and blood clots in the toilet, as well as some bright red blood. I don't think I tore anything because I didn't feel any pain, just abdominal cramping and general discomfort and nausea (which I regularly have). I am not on my period, I ended that two weeks ago, and the blood I am 100% sure was not from there. I'm 16, and I'm not in school right now, otherwise I would ask the nurse at the school. The first time there was so much blood that the water was fogged up to the point where it was very hard to see through. The bright red blood is not as dominant when I go now though, but there are still clots and blots of it. My stool is black and it's very uncomfortable to go to the bathroom because (this is gross) when I try to the stool works out about four inches but just sticks there unless I get toilet paper and pull it off. I have a very healthy diet and I am also on medication for stomach ulcers. My parents are out of state for a wedding, I have called them and talked to them about this but their return flight is three days from now. I have a permit but not a license, meaning I can't legally drive myself to the hospital to get it checked out. Please, any advice you can give me on how to deal with this would be helpful. I don't know if it is caused by my new medication or not, but I would hate to stop taking that now as it's just starting to work.