I have a blood blister on my inner labia, which I noticed shortly after having DD1, but she was born by unplanned C section, so doubt it was related to the birth. I only noticed it by looking at it accidentally. Had it checked by doctor, who couldn't have cared less! She said she could burn it off or lance it or something that sounded scary, but she said it was unnecessary, so I didn't bother. It's grew very slightly for 2 years, then leaked some blood out and is smaller and flatter now, but haven't looked at it for a few months. Maybe i should? I guess like any spot-type thing, it's worth getting it assessed and then sometimes montoring it in the future for major changes, but sounds like you need not worry too much if it's not bothering you.