Hello,
I have had two lumps, one was a bartholin cyst on labia, the other more recent, a bit further out, was most likely, according to gynae an ingrowing hair that caused a lump. The first was definitely benign and went away and the other, as it seems to have now got smaller is probably nothing too. I guess what i'm Saying is lots of lumps and bumps can appear and are nothing ominous. Like you when I got the first one I panicked but the doc knew it was a cyst straight away. As cysts sometimes have to be removed it would suggest they don't always go away on their own.
It sounds like you may not have shown a gp yet, if not i'd muster the courage and have them put your mind at rest. The spotting could well be totally unrelated.