Ladies I need your help please !

So I've had pregnacy scares in the past .. But none of them came out positive . I am irregular when it comes to my periods . My boyfriend and I always have protected sex. Recently I've been feeling very nauses and light headed .. I've been gaining a couple of pounds (not drastically) but it's still there. I am constantly hungry more than usual. I'm super moody and feel dehydrated all the time , even though I drink plenty of water . I have not gotten my period in over a while .. I'm scared that this might have something to do with me possibly being pregnat ..