How long will it take for me to come back with a vengeance?

Hey guys. Basically I've been out injured since early April. I last raced on the 15th after a dodgy 2 weeks out and since then, I've done my usual cycling (about 50 miles a week to school and back) apart from a couple of weeks off when my bike broke and I was doing a bit more than usual on top of that as well when I felt like it, but nothing major, perhaps an extra 20 miles a week or so as well as doing stuff on the exercise bike. I had shin splints/stress fracture which has persisted and I didn't realise I was probably making it worse. As the pain subsided, I was gently returning to running on and off and between April and June I probably ran about 7 times, always very slow and max 3 miles on grass/road but the pain usually came back and I had to keep resting for longer, trying again and it coming back etc. Looking back, I came back too hard and fast everytime. 

I'm a 17 year old male, and in March I ran a 37:30 10k. I could run a 5 minute mile in training and ran a half marathon in January in 1:33 and could have ran faster if I pushed harder. I started running in March last year and have done a few races since then, mostly early this year when I joined my club in January. My training only became structured in September last year and I ran a 10k in 41:30 in December. This is the only sport I really do seriously and have ever done, it's what keeps me fit and I love it so the past few months have been hard.

My training plan by the time I was injured was 1 track session per week, usually just about 3 miles worth of speed intervals, I'd do two easy 3/4 mile jogs, a fast 5k or 10k run or another interval session, a long 10/11 mile run steady and a hilly run usually about 8 miles or so. Looking back it was too much too soon as last year I was only doing 4 runs a week, two fast two slow.

I found out serious issues with my gait were probably what caused my injuries. I've been out of cycling for 4 weeks now completely, did about 2 weeks of gentle running and climbed Mont Blanc in July when it improved but it came back again shortly after and is still here now. I've been doing hard stuff in the pool for the past 4-5 weeks.

I've been told I should be able to start rehab running in about 2 months, which will just be slow and gradually building up again. Then I need 2 months of easy/gentle running before I can build up hard traning again... Does this sound right? 

I feel as unfit as I was when I started running. Can anybody tell me how long they estimate until I'll be back to my old standard of 37 mins? If I start hard training in February again and build it up. I know it's hard to tell but if you could make any estimate and advice about my recovery/training for the future then that would be very helpful, thanks

It's hard to advise you, because you seem to have put a decent amount of thought into your training schedule already and you've been given advice (from a professional, I presume?) about how long recovery is going to take.

If you've been doing plenty of hard work-outs in the pool, I can't imagine your current level of fitness is nearly as poor as you fear. I'm a bit puzzled as to how cycling might have been preventing your lower legs from recovering. Your previous training schedule looks okay to me - I'd do more cross training personally, but different regimes suit different people. Make sure your longer runs are at a slow enough pace and you give yourself some rest before and after races (at risk of trelling you the obvious).

The most important thing is that you think you've got to the root of why you sustained the injury in the first place.

At your age, you should heal quickly. It always takes less time for fitness to come back than to build it up from scratch.