First 5k in one week. Still can't run 5k!

I've been following C25K and finished it much later than planned due to an ankle injury that put me out for two full weeks right at week 8. I had hoped to have at least 3 weeks of extra training time. I've been on holiday for week and won't be back home until Tues and my race is on Thursday.

I graduated from C25K last Saturday as I did two runs on holiday but the terrain was really tough and uphill so whilst I ran for 30mins without a break, I only managed 2miles on both of my runs.

I'm hoping to be able to run tomorrow and again on Monday on a flat stretch but is it too late for me? Should I try and hit a 5k run before my 5k race? I'm concerned that I can only run 30mins and will need at least 40mins to complete the 5k. Help!!!