lump like spots on inside of bum cheek!!

[SusanFarnell]

this is going to sound like a daft question, but i have recently been noticing red lump like spots that appear on the inside of my bum cheek, not quite at anus but where pant line sits, i have had few over the past few months. usually blood stained fluid/puss comes out and then it disappears, just wondered if any1 else has had the same problem! i do shave, but not down that far (well that i notice) so i did think of ingrown hairs, but not quite sure!!advice would be good!

Thanks in advance
Susan