TTC at 42 with IVF

Ilean

Hi I am 42 and hubby and I are starting our IVF journey this cycle. I was given birth control to start off with I am on my 5th day. Question is I was supposed to have my period 2days ago and nothing yet is it normal or is the birth control supposed to stop my period for the IVF process? Not sure what to do hopefully I will get my period today