Lobby: How am I doing?

I'd recommend a strong club to get use to riding a foot or so off the back tire of a strong racer.  They may have club races or hard flat rides to give you a better idea of your fitness level. Your flat terrain speed should be closer to 24 to 26 mph.  This isn't as critical as learning to stay on the wheel in front of you.  Your buzz from just being in a group going fast will allow you to excede any speed you will do by yourself at this point. 

There is nothing wrong with jumpimg into a Cat. V crit but don't get discouraged if you get dropped in the first few laps because you aren't comfortable holding the draft/wheel. 

The criterium is a very intense interval workout even at the Cat.V level with a lot of jumps out of the corners.  You will be at LT+ for most of the race.  Stay in the top ten to fifteen.  Any further back and the race will get dangerous and very hard. 

A hard 1.5 minute on/ 1.5 minute off interval workout of 20 to 25 intervals (about the number of hard jumps to expect in a 35-45 min.Cat V race) will help give you a basic idea of the intensity level to expect. Warm up at least 20 minutes before and cool down the same after. Proabably should be done in your 53-15 or maybe 14. Intervals should be put into your workout once a week.  

You have to start some where.  Racing is the fastest way to get fit and fast.  I've got twenty years of racing so far, and there's nothing like crit racing once you get the hang of it.

Good luck.

You may also want to consider straight road racing if corners give you problem.  I noticed you live near the Wisconsin border.  You may want to try a WISPORT event.  There are time trials and road races almost every weekend starting in May and going into September.  Join a club or race team to learn the finer points of racing in a pack to conserve energy.  Enjoy racing.