Bleeding between periods. Sorry its gross.?

Bleeding between periods. Sorry its gross.?-For the past few months I've been bleeding between my periods. Bleeding tends to start about a week after my period ends and continues on various days until my next period. It's just a little blood each day and brownish in colour but its not very nice and I don't know if anything's wrong with me? 

I'm not on the pill, haven't spoken to my doctor about it. Should I? 

Also I have noticed that t seems to be once I started heavily relying on tampons that this has started and also my period has gotten shorter since started relying mostly on tampons. Could this be the reason?

  I know this may be a stupid question but you have made sure you have taken the last tampon out havent you? Its just that I know someone who got toxic shock from tampons. You really do need to go to the doctor with this one though as it is something I had a few years ago. Mine turned out to be the after effects of the depo injection but it can be a sign of harmless cysts or polyps or in a small number of cases cancer. Please see a doc and I hope its something simple thats causing your problem......in the meantime if you are bleeding continuous my doc told me to go on iron tabs or you will feel knackered!!!