I've been on glow for a while I don't participate of the forum much, this time is different and I'm confused.

So glow predicted my period would come two days ago, it's usually one or two days early, so on Tuesday I didn't get that feeling that you get in your belly when you are about to start, but I went to the restroom and there was this brownish blood when I whipped out after I peed (sorry if I'm being too descriptive) so I said "okay it's time" and I put in a tampon, about six hours later I took it out and the top of the tampon was a little brownish bloody but the rest was just wet like yellowish but didn't smell or anything, so I decided not to use another tampon. On Wednesday at mid day I went to the restroom and there was a little blood when I wiped so I used another tampon, when I got home about 4 hrs later I took it out and only the sides where a little tinted but not much really and when I peed there was a little blood coming out and a bit of what seemed uterine tissue, so I used another tampon, at night I took it out and it was completely dry, yesterday morning I took a pregnancy test and it was negative, today I did the same and it was negative again, no blood whatsoever today... I need to mention that I'm 27, we've been TYC for years, probably 3 years now and since I got my period when I was 9 this has never happened before, my periods are usually heavy and painful. Last month I spotted one day before I started but then everything was normal. 

I'm confused, I want to be pregnant but I'm also worried it can be something else, something bad because of the negative tests.

Has anybody gone trough the same?