two positive tests and now negative tests?

so, I had spotting on November 25th, thought maybe I was ovulating or it was implantation bleeding.. took a ton of tests. like every couple of days. had a positive test on December 3rd. and another one on the 6th. but it was faint. not as positive.. now, I keep testing because I'm anxious. and they're negative? anyone know what could have happened or have had something similar happen to them?

feeling super sad. because I got excited about another baby. and now I just don't understand.