I'm 40 weeks and keep getting vaginal discharge. Is it a show?

Very common. Vaginal discharge is very common in late pregnancy. If it is itching or burning it is likely something that can be treated, but if not it is likely physiologic (normal). If the discharge contains blood you should have it checked out by your physician or hospital labor and delivery.
Call your OBGYN. Most likely it is show, but need to make sure your water is not leaking, if you were my pt you would be induced, a recent large study shows the ideal time for the baby to be delivered is 39-40 weeks ! you have nothing to gain by going past your due date and potentially a lot to lose! and if u go past u need monitoring of the baby with nsts and complete OB us with a bpp.