Brown discharge. Should I be concerned?

Almost 7 years ago I had a tubal ligation after having my third child. I had heavy periods, but on time for about 2 years. Since then my periods have been more normal & still on time. There were a few times I would go to the bathroom & see a whitish mucusy ball on my underwear but didn't worry about it because I had no other symptoms of an infection & go to the doctor once a year (had gone in Feb) I had a period the second week in April & everything was normal. Two weeks later I had a large (about a quarter in size, but long) red blood clot come out & then had some brownish discharge a few days after that just a couple of times when I would wipe. If I would wear a pad there was nothing on it. This month I was late by a few days. I just happened to go to the ER for strep throat & they did a preg test so I could take narcotics & get a penicillin shot. The test was neg. Now I'm having a lot more brown mucusy discharge. No cramping. No smell. Should I be concerned?