What Causes Inconsistencies In Periods?

hello, i am a 25yr old women with usually regular menstral cycle every 28-30 days lasting 2 days. The last 3 months i have been travelling overseas. The first period i had since being away was 20 days into my cycle very watery, bright red lasted 2 or 3 days, the next was day 31 much the same as the first then heavier on the 3rd day. The latest one was day 31 also seemingly regular period lasting 3 days then nothing yesterday, this afternoon i felt increased need to urinate and when i did two small blood clots were in the bowl and since then i have had watery bright red vaginal discharge. please help if you can