White Cratered Bump And Feeling Sick?

So about a week ago I discovered a red little bump in my pubic hair. There was a hair in the middle of it so I pulled the hair out. Now about a week later that bump is bigger, but it's like...picture a moon crater. It's like that and it's white in the middle. Two days ago I woke up and felt bad. I still feel bad today. My lower back is sore, I'm very tired, and I've had super watery diarrhea since yesterday. The thing is the symptoms have been coming and going. Like last night I felt fine after I had been feeling crummy all day. Then I woke up feeling crummy again. My appetite is still there, I've been eating fine. Have been drinking a lot more fluids then usual because I've been thirstier. I feel very sleepy and fatigue. Also when I take Ibuprofen it really seems to help the soreness in my back. I haven't had a fever, but I have been getting very cold, then I'll get very hot. It's weird. Any idea what I've got here? I'm planning on going to the doctor so don't just say that. I'm looking for a bit of information is all although after reading up I think I may have syphilis. There is a pinkish reddish looking rash around the cratered bump. It is not very big, however when I touch it it feels like there are bumps there, but I can't see any. Please help me. The bump is also somewhat itchy, but only for a split second. Like it'll feel itchy then it suddenly won't anymore.