Hi mb9252,
While you're probably not feeling too good right now (which is understandable), you're not the first person to score lower than they wanted on Test Day, so let's look at all of this as a learning experience and figure out what you can do differently next time to score higher.
If you can provide a bit more information about how you studied, then I'll be happy to advise:
1) Did you really study every day for 4 months (or were there "chunks" of time that you didn't study?)?
2) What resources did you use?
3) Were those 2 CATs the only CATs that you took?
4) What were your Quant and Verbal Scaled Scores on those CATs?
5) Did you take the Essay and IR sections on those CATs or did you skip them?
I'd also like to know a bit about the lead-up to Test Day and Test Day itself:
1) When did you take your last CAT?
2) What did you do the last 3 days before your GMAT?
3) How did you sleep the night before your GMAT?
4) What day/time was your GMAT?
5) How long was the ride to the Testing Center from your home?
Thankfully, the GMAT is a predictable, standardized Exam, so you CAN train to score at a higher level. Clearly, some adjustments to your approach will have to be made before you retest - this will require some more time and some new resources. Since Business Schools don't care if you take the GMAT more than once, there's no harm in doing so.
GMAT assassins aren't born, they're made,
Rich