Lots of good advice going out to you. One warning I have not seen - cycling can be a very expensive sport. That's why the advice to get a cheapie or good used bike is very good advice. At your age, the bike is not going to slow you down! If it helps, I rode a cheap hybrid for 3 years until I could afford a road bike, then ended up buying a used Trek 2300 for $400. I have had the Trek for 6 years and see no reason to replace it. I just keep upgrading. Working in a shop you should come across a lot of good upgrade opportunities at a good price. Of course, that's why cycling can be an expensive sport. Then there are shoes (good ones are $200-$250), pedals ($100-$300), helmet ($50-$200), clothing (shorts, gloves, socks, warmers, covers, jackets, etc), tools, tubes, tires (good ones are around $50 each), bag(s), glasses, wheels (you'll envy the people with the high end wheels), etc......

Missing one cycling season seems tough right now but won't be a big deal the next season when you have that new ride to use. Ride junk now, get what you want when you can afford it. Let your mom buy you some of the good upgrades when she sees how much you enjoy biking!

Hope that helps.