At 13 with 8-months of experience, I would think it is unlikely that you are hitting a proper flat first serve. Your best bet is to develop a slice serve first. This can be used both as a first and second serve. It is easier to learn than a flat serve and more reliable. You will also be surprised how effective the slight amount of movement is in keeping your opponents from going on the offensive.
It will also force you to be in the "palm down" position at the top. This will make it much easier to transition to an effective flat serve with proper form. A topspin serve is very similar to a slice so this will be an easy transition as well.