No AF and no period

I had a chemical in March and bled 3/11. I was suppose to start my period yesterday and I didn't. No sign of her. Anyone had this happen? Should I be worried? I took FRER pregnancy tests and they're all negative. I'm starting to worry. I called my doctor and she said if I don't start in two weeks to call her but idk if I can wait two weeks to see if something is wrong. Also, I am very regular. I'm never late. My cycles are always 27 or 28 days long. My doctor didn't want me to try this last month so we didn't so I don't think I'm pregnant I just don't know what's going on