ANY MEDICAL PROFESSIONALS!?!? (nurses,doctors, etc.)

My boyfriend and I are both 20 and are both in college (biochemical and engineering). I am on birth control and we are both clean. Is it even that big of a chance that I could get pregnant of we didn't use condoms all the time? We are both clean, got tested.

It is just so much better without a condom since I need to keep putting on lube on with the condom. Without it is perfectly lubed.

What are the chances I could become pregnant? Can precum actually get me pregnant on the pill? What happens if I miss the pill one day and have unprotected sex the next days after?