If you have more than $400 of self-employment income, or more than $12,000 of earned W-2 income, then you would be required to file. So long as your $2K of income is not self-employment income, you don't need to file. However, if any taxes were withheld from that $2K of income, you should file so as to get those withheld taxes refunded to you.
Just keep in mind as TGBill pointed out, that if more than 50% of your support was provided by other means, such as a combination of food stamps, welfare or other government assistance programs, then there's no way your son provided more than 50% of your support.
But if your son does qualify to claim you, *and* you will be filing a tax return, then it's important that you indicate on your return that "I can be claimed on someone else's return".
