1 week till 1st race ever (10k)

[chickensrun]

Hi, I'm quite a newbie running, having only regularly been running for 6 weeks! I'm aiming for a half marathon, and have signed up for the Bewl Water 10k a week today as part of the training/to give me experience of a race.

I've only run 10k once (3 weeks ago), today I'm running 10k. Don't know whether to run it as a full-race practice (seeing if I can equal my pace/time 3 weeks ago), or whether to go slower so that I've got more in the tank for the actual race.

If I do that though, how do I know what pace to run at in the race next week?