I'm going to be totally honest here: It's not a masterpiece, but considering it's your first, it doesn't need to be. I'm a student learning flash at the moment, and I know how hard it can be to learn. I'm certainly not going to be posting any of mine soon, not the boring crap we have to do in my school.
Having said that, I can offer some helpful hints. The looping is pretty much a part of any Flash animation without code- it's the default. You need to use actionscript to turn it off.
It's very simple. It's generally good habit to have an entire layer dedicated to nothing but code. Name the layer 'actions' and make sure to keep it the top layer. Make sure the actions layer has the last frame of the animation being a keyframe, and open the actions panel. You should find it under window. All you have to do to stop the looping is go to the last frame (remember, it needs to be a keyframe) and type "stop();" in it. It must be typed exactly like that, but without the quotations. Actionscript is very picky, and even capitalizing it will make it not work.
In addition, you could also put the frame you intend the animation to stop at inside the parentheses if you so chose. For example, if you want the animation to stop at frame 115, you could write "stop(115);"
If you want to do anything beyond basic animation like what this is, you will have to know actionscript. Even simple restart buttons or such require it. It's fairly easy to find tutorials on google, and the basics are incredibly simple.
Alright! This was really helpful, thank you for taking the time to type all of that out :) I'll make sure to fix it in the future. And good luck to you too.