Confused. :(

I have taken a few test the last week or so. I was suppose to have my period yesterday, and it never came, but it has not been consistent since I had my son (who is 15 months). :( I have taken 4 dollar store test that were positive yesterday and the day before, but two first response were negative. And today I bought more dollar store tests that were a different brand, and they were negative :( ugh I don't know how to think or feel. Could it just be early still? Trying to see my dr as soon as they will get me in.... But am I setting myself up for disappointment?