First Pregnancy

I am pregnant with my first pregnancy ever and I went and had my blood drawn this morning. Doctor called and said HCG levels look great for how far along I am, but said my progesterone level was 7.5 which is a little lower than they like. She said they are calling me in a prescription to start of progesterone 200mg.

Is this something I should be worried about?? I am just super nervous because my husband and I have been trying over a year and finally got a positive test.