Best Route

Hi guys ive been training for plymouth half for about 10 weeks following bupa training plan, this is my 1st half marathon. Training has gone ok upto when i did 8 mile 2 weeks ago where i got pain in my leg knee, I think i have that band sydrome where ive over trained. I have trained since saturday doing 2 mile on tred every day with 8 mile on the bike and my knee has been fine. Went to running shop today and got told my trainers were really bad so no been advised some better ones but not sure how i should train as i have only 6 weeks till the race. Any advice most welcome as training was going really well before the niggle but want to train best i can without irratating the band. The guy in the shop said it was probably my trainers as when i run my left knee goes out and not in line yo my feet but the new trainers have sorted that out. How mant times should i run a week and whst should i do on them days, thanks