First 5k suggestions?

So this sat I'm running my first 5k I have been doing the couch to 5k I'm at the 8wk mark still have another wk to go on that but sat isn't a wk away anyhoo should I just run 3.2 miles tomorrow to see how long it takes me?

I have ran several 5ks and 1 10k, if your race is on saturday I personally would do a nice easy jog do the 3.2 miles if you want, I wouldnt push too hard or you may not perform your best on Saturday. I wouldnt focus so much on time either, it is a feat just to be able to finisih it, and then you have something to strive for next time around it is a lot of fun to see if you can beat your times :)

What's the furthest you've gone? If it's not close to 3.11 miles (5K) don't pu**** or you might get injured. The purpose of a couch to 5K program is to increase time running continuously rather than mileage. So if you can run at a 10 minute mile pace, you'd complete 3 miles in 30 minutes of continuous running. But, if you are slower the same 3 miles takes more time so you may be running longer than the 30 minutes of continuous running the program assigns. I would stick to the program and see how far you can go running continuously. 

You've almost finished the program.  Assuming you're on track, I say push yourself a little and go for it.  You might be a little extra sore the next day but I think it's unlikely you'll hurt yourself.