Please try not to worry yourself too much although I know that can be hard, hpv testing is relativley new and in days gone by a borderline result would have most likley been monitored with a repeat smear in 6-12 months. Nowerdays they are a bit more on the ball and that can only be a good thing, so now a boarderline result coupled with hpv+ means a colpo just to be on the safe side and to monitor what is going on more closley.
Obviously I cant say what your outcome will be but at the colpo they will take a much closer look at your cervix and apply some solutions that highlight any wonky looking cells, if they spot anything of concern they will take a biopsy just to check what is going on and to be on the safe side. If anything turns up there is still the possibility that early changes can revert back to normal by themselves, and often they watch and wait to avoid unnecessary damage to your cervix, especially if you want kids in the future.
I am not a doctor but I am under the impression that CIN1 isnt quite the same as a borderline result. CIN can only really be diagnosed by a biopsy as smear results are more of an indicator than a diagnostic tool. A boarderline result means that some cell changes were seen but were very near normal.
I hope this makes you feel a bit better knowing that now you are in the system they will keep a good eye on you to make sure that nasty cell changes dont get the chance to take hold. There have been quite a few topics recently by women in a very similar situation to you so having a mooch around the boards might help to put your mind at ease, rest assured you are not alone my dear and we are all here to support each other through this.