Implantation bleed or period

Okay so I need help! Please! I am pretty new at this hole pregnancy thing... I have been very lightly bleeding for 6 days now. It's not enough to use a tampon or a pad ..... I put a pantie liner on just to be safe but nothing gets on it. It's very light pink some times it's red.... I usually have very heavy periods. I been very nauseas, threw up a few times, headaches, some foods make me sick and I'm very tired.... No energy!  Yesterday I had light cramping but today it's gone! I am very confused about what's going on! I JUST FEEL VERY DIFFRENT .... did a HPT 2 days ago and was negative... Please help me!