My boyfriend went to the doctor yesterday and found out he has genital warts I asked all my sexual partners (there weren't a lot) and they all were either tested or are in relationships w/ girls who have been tested and none of them seem to be infected. I

Warts in couples. Genital warts can appear months or even years after catching HPV, so you might or might not be the source of his infection. Either way, you've been repeatedly exposed and probably infected, so condoms won't make any difference now. The main thing is to keep a lookout for warts and see your doctor if something shows up. Or you can go for exam now to check for unnoticed warts and pap smear.
It . It will be difficult to know where he got them. Mouth burning after oral sex is not a common finding with contracting genital warts. He may have gotten them from a prior sexual partner as well, as they don't always show up right away. The most important thing is that he treats them completely, and that you both always use condoms to prevent infection. You should also have a gynecological examination and let your doctor know about your concerns.