Does your tongue always swell when you get it pierced?

Yes and if you don't keep the swelling down by following the aftercare instructions given to you by your professional body piercer you run a good chance of choking due to the excessive swelling.

In all honesty it feels like there is a football in your mouth for about 7 to 10 days,but in the end its definitly worth it.

IMPROVED ANSWER- If the swelling doesn't go down, but instead gets worse, what could happen is the tongue will swallow the barbells at the end of the piercing. This could require surgery to fix (don't worry, it's not life threatening). If you notice the swelling does not go down, ask a professional for treatment advice. It is very unlikely you will end up choking on your own tongue.