whats going on with my cycle? please read, i'm 19.?

[Jemma B]

Since i got my period when i was 13 my cycle has always been irregular. Its been between 28-50 days long. Only twice i've gotten my periods on the 28th day which was about 3 months ago. And i only ever got them on the 50th day once which was a few months ago also. So i'm taking it that 28 is my shortest cycle and 50 is my longest. I only finished my cycle last week (I got them the 40th day this month) and yesterday i got them again! which means my last cycle was only 15 days long. It started coming out brown then bright red and now brown and red and its getting heavier which normally gets lighter towards the end of my period. Whats going on? could my cycle start to be regulating?? I hate having irregular cycles. Did i even ovulate in my last cycle? because i remember the day after my last period stopped (which was last week) i was very dry down there which is unusual for me then and i was like that for the week until this period started so more then likely i didnt ovulate in that cycle. My biggest worry is that i dont ovulate and ill have big problems in trying to concieve. Me and my partner haved talked about trying for a baby soon in maybe a year or 2, and i'm afraid it wont happen. What do you think is wrong? My mother always told me that as long as i'm getting my periods i'm working lol and im ovulating. I had unprotected sex the last 3 days of my last period which i thought this period was implantation bleeding since it was so light the first day. Could i still be pregnant and still be getting my periods? I had unprotected sex a few weeks ago also. Today i feel so tired and exhausted and feel a bit nausea, and a bit bloated. Ive been also getting slight headaches too.