Can you get pregnant if a male ejaculates twice inside you two days before you're supposed to start your period?

Unlikely: unlikely but possible given that you can't be sure when your period is going to start. The follicular phase (before ovulation) can vary from cycle to cycle and that's why you will need a second method of contraception even if you use the time method of you don't want to be pregnant. I'm sure your doctor will be able to explain more to you but I hope this helps.

Pregnancy Likelihood: Many things affect chances of pregnancy. Volume of semen & the estimated date to start a period are only two. Ovulation (when an ovary releases an egg) can take place almost any time in a woman’s cycle. The egg travels down the fallopian tube and may be met by a sperm, become fertilized & leading to pregnancy. Bottom line answer to your question is “Yes, this is possible but not guaranteed”.

Possible but: Very unlikely. But some women, particularly those with irregular periods, may ovulate at variable intervals including close to the time of menses.