First of all don't worry about being trigger happy . That is normal when you havn't had much sex as your appendage will be very sensitive . Also don't worry too much if it doesn't quite work out. Many including myself felt clumsy and unsure the first time we had sex.

Because you havn't stated it I am assuming that your girl isn't taking any form a contraception like the pill .

I applaud you for using condoms as these are vital as both of you will be very fertile at your ages.

As you pointed out you are both very nervous, I would do some sort of activity when you are both naked so you can get used to seeing each other in the nude. I am assuming here that neither of you have body confidence issues. If so adjustments may need to be made . A good nerve settler is playing something like Naked Twister which will get you both laughing and more relaxed. Just a note of caution . When you are stiff you may notice precum discharging as you will be sexually excited . Its important that you keep this way from your girls vital area as it will contain a small amount of sperm . Enough to get a girl pregnant if you are not careful .

If your still hard I would recommend that you get sheathed up before you start anything intimate and make sure your hands are thoroughly washed and free of precum .

My late father advised me in one of his "penny" lectures that a woman's body is like a new car. It needs warming up first and this is were foreplay comes into play. A woman's body has many delicate areas apart from the obvious ones. Sometimes the ears and ear nibbling can be a turn on. Another area is the neck and also the inner thighs. I would caress and kiss these areas first before stroking her obvious parts. What you are trying to achieve is to get her body ready for making love. A good indication of this is when she gets very moist in her delicate area. Because your so trigger happy it may be a good idea to limit her touches on your appendage as you don't want to shoot your load too soon.

When she is ready probably the easiest beginners position is going to be the missionary position . Check it out on the internet if your unsure how to position each other . It may best for her to guide your appendage into her . Once done then try gentle rocking movements until you shoot your load.

Once done don't be hasty to fall to sleep . Cuddle your girl and reassure her as she could be quite emotional . Before both of you settle down to sleep it may be a good idea to shower and get yourselves cleaned up .

If you feel confident enough try morning sex the same way.

Good luck