[cliffbeall]

RNA will not run on a gel exactly according to its size because it is single stranded and the secondary structure can be variable. To get an accurate size you need to use a denaturing gel (formaldehyde, urea, methyl mercury) and compare it to RNA standards.

Since you see 2 pretty sharp bands, your RNA is probably fine.

Edit: There is also a bioanalyzer chip for RNA that would be an option if you have access to an instrument.