There are a few points that need to be mentioned.
1) Your boyfriend may not want you to go to jail. In most states he is under the age of consent and therefore ANY sexual activity between the two of you could result in a statutory rape charge.
2) I've said this many times, NO ONE should engage in sexual intercourse until they are emotionally, financially and physical ready to have a child. I suspect the main issue for your boyfriend is that he does not want to be a 16 yr old father.
3) At your ages having a boyfriend younger than you is unusual. And your boyfriend may have some apprehensions about that.
4) There are other ways to satisfy your horniness. Cold showers is just one of the things that come to mind. ;)