I am a teenager, and I have some advice.
I know my profile states that I was born in 1985, but I am very protective of my identity over the internet. I use the year 1985 as a default date of birth.
I think that it is alright to kiss when you are a teenager, especially if you have already been dating for six months. Buddha once heard a man explaining strings on an instrument to another man: "If the string is too loose, it will not play, if it is too tight, it will snap." I think you should find the middle ground. In this scenario.
I have been raised with a lot of atheists, and I have heard of many people engaging in sexual activities with multiple partners simultaneously. I believe that this is terrible. At the same time i know of teenagers having very intimate and sexual relationships with one partner for a number of years. I am not advocating that you engage in anything but kissing with your boyfriend, especially because you are a young teenager, but I do believe that it is important to establish sexual chemistry with someone before you marry them.
I think that sex is a very important part of being human, and that if you are going to make the commitment to remain with someone for the rest of your life you should ensure that your sexual connection is a strong one.
It sounds to me that you and your boyfriend are very careful about resisting temptation. I think that if you were to kiss and keep your physicality at kissing it would be proof that you are mature enough to handle kissing. If you find yourselves going too far you will immediately know and you will have the strength to stop. If you don't have the strength I am willing to be shame will stop you in your tracks.
I hope that this helps with your decision, and I hope you make the one that works for you!
-Zalen