Idk😭

So my period suppose to come today but I've been thinking I'm pregnant even though I took 3 pregnancy test and all came out negative..my cervix is low and closed but I was checking like 3 days ago and I had a pink discharge and I stuck some paper in there and here was a little blood and it's been doing thats sense....what can it be..or its just me checking it often with paper and it's irritated PLS HELP