I don't know, but couldn't it be an ear infection? My DD had one and her eardrum burst, and a little (not as much as you described) blood came out. She also felt a bit better at this point because the pressure was relieved.
I had taken her to the ped at the first sign of infection (before the eardrum burst, and within 12 hours of when she most likely actually got the infection). He prescribed antibiotics. Then the eardrum burst a day or 2 later, so obviously the antibiotics didn't work. Took her back. Stronger antibiotics and ear drops. Didn't help. A week later she was still on them (and I hated every day of it, but wasn't sure what to do) and she had blood in the diaper. I saw the oncall ped on Christmas Day and took the diaper in, and thank god the ped said to just stop all the medication immediately.
Anyway, I told you all that since even if it could be an ear infection, I don't know if going to the ped is the best course of action. They'll just prescribe an antibiotic and I've since read that they don't even change the course of the infection about 70% of the time!!!!!!! The fact that they help 30% of the time is respectable, but given the dangers of antibiotics shouldn't we be so much more careful about prescribing and using them?????
Homeschooling mama to 6 year old DD.