Blood at the top of my dildo after anal masturbation (male)

Hello, 

I'm a 17 years old male, virgin and heterosexual. 3 weeks ago I decided to masturbate anally with a carrot (I did it in the past without any problem) So I first used my fingers (with uncut nails, I know it's stupid) and then I used the carrot without a condom, and just with my saliva to lubrificate it. I did that for maybe 10 minutes before to stop and when I pulled the carrot out, there's was blood mixed with mucus at the top of it, just a bit, no flowing and only on the top. I didn't feel any pain or anything. When I went to the bathroom I didn't check if there was any blood on the toiled paper but I don't think there was. I felt no pain, really nothing and 3 weeks later I still had no problem, except being sick one week after the event, I had diarrhea and I was feeling sick but I think it was just a gastro enteritis. And since then, I have nothing, no pain, no blood, just nothing but I'm worried as f**k. I need to say that I'm having a treatment of roaccutane since 8 month so my mucosis (I'm not sure about the name) are very dry and I know we all have some in our butt., that's maybe why there was blood. And that my nails weren't short enough when I masturbated. So there you know, I hope it's nothing serious (like a perforation of something or I don't know what...) because I'm really worried and I can't really talk about it to my parents. Thank you in advance !