After having sex five days ago, my outer labia became swollen and very tender. Although slightly red, there are no markings of a rash. There is a small mass under the tissue. It is nothing like an ingrown hair or pimple, just a solid mass somewhat deep underneath the skin. The majority of the swelling and tenderness is toward the back of my labia, not the front. (as in farthest away from my bellybutton.) I'm in a decent amount of pain, as it is uncomfortable to sit, walk, or even stand. Do you have any idea as to what may be causing this? Do I need to see a doctor?

If I were having as much discomfort as you are having, yes, I would see a doctor. And please report back after you find out what it is and how to treat it.

Yes, Wondergirl, I think you're right. I called to schedule an appointment with my ob-gyn, but I can't get in for another week. Im not sure what to do do until then. Do you think it is all right to wait that long?

Don't don't think you should wait a week to have the mass diagnosed. Is there a clinic you can go to ?

Thanks to everyone for the advice. I FINALLY was able to see a doctor This week. Turns out, I had an infected Bartholin's gland. This is a lubrication gland that all women have in the outer labia. For many women, it can become blocked and infected from time to time. Nothing causes this to happen, just mother nature's funny sense of humor. I was sent to the ER, where they drained the gland. Im now home resting and on some serious pain killers. If any of you ever experience similar symptoms, please don't wait for a doctor's appointment. Just go strait to the ER. It really is a very common problem and they knew exactly what I was talking about before they examination ever began.