Injured just before first marathon. What next?

So signed up to the cork marathon and a completed a 20 week programme. Was looking to do as close to the 4 hr mark with the dream of sneaking under 4. However on my last long run of 26k I had to end it at the 20k mark due to shooting pain on the outside of my hip. Had a similar problem a couple of weeks previous but after a few days rest it was fine. Thought it was just down fatigue. I had done 50 odd kms over 4 nights. However dispite resting it for over a week with just an easy 5k in between it didn't feel right. I knew I would not finish the marathon so made the call to pull out.

I'm going to go to the physio this week for advise. I'm hoping this can be resolved in the next couple of weeks and start training for another marathon. I'm thinking of the galway bay marathon in October.

The question is where do a start on my marathon plan again. Do I start from the beginning? Here is a brief outline of what I did.

20 week programme.
1st month was 5ks slowly upping the mileage. 5 runs a week
Then it was 4 runs a week as the mileage increased.
The highest mileage was 70k which i done twice. This included a 20 mile run.
The midweek runs ranged from 8-13km. The pace averaged 5-5.30 mins/km depending how I was feeling.
One of the runs was on the treadmill where I worked on pace. Usually 1km at 14km per hour and then the next at 10.5km to recover.
Regarding the long run I only realised you had to go 45 secs to a min slower than your targetted pace until half through the plan.

As I said previously there were some weekends where there were events on so had to cram 4 runs in a row during the week. What do people do when they can only run certain days during the week? I understand how important rest days are. Should my midweek runs be slower?

Any pointers or advice would be appreciated