Thank you for that additional information and pictures.
Unfortunately, the pictures are out of focus and do not allow any fine details to be seen.
That being said, a blood blister would have gone away by now.....
So. What to do?
I would make a point of mentioning it to your doctor so that she can take a good look at it in person. It would be useful to make an appointment to specifically have this lesion evaluated so you don't forget to talk about it again.
While sinister things, such as melanomas etc, do occur on the lip, this would be an usual location.
Here is an excellent article from a highly respected source that goes over the diagnosis of pigmented lesions in the mouth and lips. It is a bit technical.....
So. What is the take home message?
I bet you will be OK in the long run but do take the time to have your MD or DDS have a look at this in person.
Does this make sense to you?
It's safe for you to press the positive feedback button now if you so desire. And, never fear, even after you press that button I'll still be right here to continue helping you, but, as I do work for tips, I want to make sure you are happy before rating me.
Dr. Rick MD FACS