Since I have hpv, does him thrusting against my cervix put me at higher risk for unwelcome changes to my cervix (e.G., precancerous cells)?

HPV. There are so many hpv virus, 16 & 18 are the most common risk type for cervical cancer. Intercourse w your boyfriend will not change to much your risk if you already have hpv. You need yearly pap smear, avoid multiple sex partners, prevent having hiv, don't smoke. Good luck.
Not likely. As dysplasia (precancerous changes) of the cervix, vagina, and vulva is due to exposure to the sexually transmitted hpv virus, any contact can transmit it.