Honestly, if your verbal score is in the 17 - 22 range, I'd recommend taking a community college class to relearn fundamentals. I find for my students that if they're consistently scoring in that range without improving, then they need to brush up on the basics before proceeding further. Starting now, I'd also recommend doing lots and lots of reading - newspapers, magazines, you name it, as part of your verbal practice.

If you're not in a huge rush, I'd hold off on taking the test for a bit. You also mentioned that you're getting exceedingly anxious - that probably doesn't bode well for your stress level when taking the test, either.

Good luck!