Sp confused please give me advice.

My lmp was 12/19 I took a test about 3 days before my expected period on sunday and there were two visible lines both had color and I got all excited. It's now 3 days past my expected period and it still hasn't shown up so I've tested again and I keep getting very faint positives but their not getting darker. Any advice on what I should do? Is it possible still to not have that much HCG? I'm so confused. At this point i wish Aunt Flow would just show up.