White rough thing in my pilonidal dimple. Help please?

I am a 16 year old high-school student, please help me.

About 2 weeks ago I started to feel some pain in my tailbone, more specifically the very bottom of it, near my butt. I do not have any problems moving, but when I sit back, I feel pain. When I sit on a cushy chair or lie down in bed, I feel immense pain. I have been working out in the gym lately because the cross-country season has ended, and my dad and trainer both thought that the pain was due to the work-outs. I thought they were correct until recently.

The end of my tailbone happens to be right where my pilonidal dimple is (which until I just did some research, I thought everyone had). Anyways, when the pain began, I felt down there and to my surprise found that something deep in the dimple felt rough, almost like a scab. Again, I thought this could be relating to my exercising; maybe a few weeks ago I happened to tear something in there doing sit-ups. Last night I noticed that my tailbone was actually feeling a bit better. Today I looked at the dimple once again in a mirror. The scab-like thing seems to have grown and I can clearly tell that it is white.

I did some research, and read some information about cysts and things having puss (which now it actually seems like the scab-like thing has inside). Then I read about surgery.

I'm already getting around 5 hours of sleep a night due to academics and sports, and this pain has not been helping at all, sometimes keeping me up until 2;30 AM, with my alarm going off 4 hours later. Maybe (and hopefully) this is not a big deal and is related to working out, but even if it is, I need to figure out why and how to make it feel better.

But if this happens to be a bigger deal and I need a procedure done, I need to know as soon as possible. I already have a doctor's appointment scheduled for the day after tomorrow, and will be showing this to him. Please tell me what you think this is. I am scared, and worried, mainly due to the fact that I'm extremely busy and missing school for a surgery will really be awful.

Other information that might be of use: I am 6'2" and weigh 132 lbs, and this is after I gained about 5-7 lbs.

I spent a lot of time writing this. Please do me the favor of responding. I need help on this. Really don't think I'll need surgery, but if you think there's a possibility that I will need it, TELL ME. I will need to inform my teachers/get extensions on tests, lab reports, and essays if I will be missing school.

[Tofurky]

I don't have any hair around the pilonidal dimple so maybe it's not a cyst. Could it be an infection?