Spotting????

I have a question for anyone who has had implantation bleeding. Last night before bed I noticed a very faint amount of blood and was expecting it since it was my day to start. So I put in a tampon then checked this morning and nothing was on it. I took a pregnancy test to see just maybe and it was negative no faint line or anything. I then took a shower and I saw another small faint amount of blood and figured since it was night maybe my body wasn't ready or something so I put in a tampon. After six hours I am changing my tampon and there was only a drop! My periods are usually super heavy for three days then one day light with horrible cramps. Right now I'm only feeling light cramps. Help please with suggestions my husband and I have been trying for over 2.5 years and am really trying to keep calm and not to excited.