You should do your own taxes if . . .
. . . you have a fairly simple return (for example, you have one W-2 from your job, maybe some student loan interest, and you paid a childcare provider to watch your child while you worked).
. . . you use some user-friendly software that will guide you through the return (TurboTax, TaxSlayer, H&R Block), if you're comfortable using that software (and what is comfortable for some people may be completely anxiety ridden for others). Some software, like TurboTax, can make difficult items like rental property or freelance expenses pretty easy if you just follow their guidelines.