it is a high chance of chlamydia but worry too much as it can be easily cured with antibiotics
I agree with rbgos -- Get to a dr. QUICKLY... inflammation and blood in that area are not good signs at all!!! (unless she had some sort of piercing and you cut yourself on it). But if you get it looked at and treated immediately (if they find that something is wrong) you give the dr.'s a much better chance to get rid of it.
Go and visit a doctor or an STD clinic. No-one here on this forum will be able to tell you for sure whether you have caught anything, that requires a professional who can inspect the area personally. Whether or not this is caused by an STD, they should be able to advise and sort you out.
Good luck, I hope the news is good...