I personally would not get into the habit of getting a girl on a pill or a shot ....or using anything less than condoms. Unless youve been together for at least a year or you are both VERY committed to each other. I still would be very careful about NOT using condoms. I would advise against it. I made this mistake ONCE and now i have HPV. (Genital warts virus). So, basically I dont have the warts...got them all removed...but I still have the virus and can give it to someone else if I have un protected sex. Yea, me and this girl were dating for 6 months. Everything was great, we were monogomous (or however the fizzuck ya spell it), etc. So we both agree it's a great idea for her to get on "the shot" so we dont need to use condoms.
Unknown to me, and I assume her as well....which is possible because a womans sex stuff is mostly inside her body and she can carry STD's internally without knowing she has them.....she had HPV. It can take a few months or longer to break out too. So, of course a couple months later, we break up. Few months after that, I start getting these little raised nodules on my penis. It was only a couple at first so I put it off. Long story short, I put it off for over a year partially out of ignorance, partially out of pride, and partially out of denial that I could have an STD even though a little voice in my head was nagging me to go get it checked out.
My best advice would be to switch to thinner condoms. As thin as you can find. I know Durex makes some called something like "barely there" condoms. Use a water based lube inside and out on the condom. This will improve your sensations greatly. Should help with the "problem" youre having too.
Also, dont use the "ah we're young" or "ah but we're each other's first fuck" excuse. You get into the habit of not using a condom now, it's that much easier to not use one later.
This reply is not a scare tactic. Just a reallity check. Youre a young guy and dont deserve to get stuck with an STD for the rest of your life right? I consider myself lucky to not have caught something much worse. Could have happened.