Race me?

Run a 5K.  That's the goal.  Now the question is...which race to run???

I am overwhelmed at the number of 5K races there are just in our area. 

I know I want to run the whole thing...no walking.  The longest I've run so far is 30 minutes and the longest I've run without stopping is 24 minutes.  My pace is between 12-13 min/mile.  Clearly, I still need to do more training so I can run the entire race.  I am kind of hard on myself because I think I should be faster, but then I need to remember that I've only been running for a month and according to my "Couch to 5K" plan I am just starting on week six, which is walk 5/ run 11/ walk 5 min.

Also, should I wait to sign up for the races until the last minute because we are trying to get pregnant?  I don't want to do anything unwise.  Of the research I've done, the studies seem to be inconclusive.  Many studies say that if you are already running then there's no problem, but just don't over do it.  Some studies suggest not running at all while pregnant, but just sticking with the eliptical, light yoga or walking.