Muliple Red Bumps On Penis Shaft

For quite a few months now I have been getting these small (size of nail head) red bumps on my penis. I first noticed one or two and didn't think much of it but since then the amount increased to about 6. They come and go in different areas but usually near the head of the penis on my foreskin. If it goes away it may take 2 weeks or so. Some of the ones i have now, have been in the same area for a few months, not going away. At the first sign of a new bump it is small like a pin head, it gets a little itchy and then a day or two it gets larger and swollen. Sometimes its itchy sometimes not. There is no white head, no puss, no oozing. Its been months and now it seems to be getting worse, usually its just one or two. Some days they are more swollen than others. When it seems to be going away, the next day its more swollen, without any cause for it (no sex, masturbation, etc)

Any ideas, i don't believe its an STD, and havent been with my partner for fear they might see it and it will cause embarassment? I have a dermatologist appt next week but would like to know if anyone experienced this or knows what it is.