What do you think? Please give me your opinions, the doctors office were no help...

Last month I was spotting for a week almost 2 weeks before I got my period, this month I was spotting or light bleeding for a week but no normal period like bleeding yet . I had a baby Oct . 1st and I've been on the pill for 2 months and I've taken 2 tests but they've been negative. I called the dr. They said to take a test it was negative. Should I go get blood work done or should I just wait it out.... my last pregnancy I knew before the test or the doctors did I don't know if I'm pregnant or if it's just my body not agreeing to birth control?