Re: when should you be tested again for HVP?
I don't know, but I would assume every year.
If you are very anxious, you could ask your doctor to order (or send you to a gyno to order) a colposcopy with an ECC (endocervical curettage). That's what I did.
I've always had my paps, ever year for 26 years, and they've always come back fine. I tested positive for high risk HPV and my doctor sent me for a colposcopy. It was fine. "Just to check" my doctor did an ECC. This identified cells that greatly concerned my doctor and eventually lead to a cancer diagnosis (adenocarcinoma Ia1). It was at such an early stage that my only needed treatment was a hysterectomy (uterus and cervix only) which I had in June.
I don't say that to scare you, but to encourage you to be proactive. HOPEFULLY your doctor has caught everything at an early stage and it is just a matter of wait and recheck.
I hope that helps!