Talk to Gynecologist on Unidentified Brownish Discharge

History: left salpingectomy on sep 17 after raptured ectopic pregnancy on 7th week. ( 1st time conception). Afterwards, regular periods with occasional visceral pain in the left lower abdomen.

Problem: Normal periods end on 2nd December, but aftet 4 days light spotting started which lasted 3 days. To be on safer side, got bhcg done and it was negative. On dr recommendation, started folic acid 5mg. Had my next periods 3 days frim the expected date on 25th December, but it was very heavy periods with 1 to 2 inches lumps. Got pelvic examination done, report were fine. Periods end on 10th day, 3rd Jan (normal for me, cycle 34 days with 10 days of periods). But now, i am experiencing visible brownish Discharge since my periods end. I am getting worried now and seek expert guidance.