Uhh what's goin on...

Hey ladies! My name is JoJo. We have been ttc for almost 3 yrs now. Nothing so far, keep your fingers crossed! But here's what I don't get... My last period was in the last week of January, absolutely not a drop in February, and barely spotted on the 2nd of March. It wasn't even a full day, so light that I didn't have to wear anything. Took a test about 3 weeks ago and got a bfN :'( and still haven't started yet. I'm so confused. So ladies all and any input on this and/or tips on how to conceive would be SOO appreciated