You're just a young whippersnapper Mike. i'm 56, and there are others older than me on these boards. Lets look at your schedule first. Looks very solid to me, and you're increasing the weight, so relax, just keep pushing, and it will go up. These things don't happen over night. Also, for your background, and goals, you really might want to check out crossfit, they don't specialize, they just go after all aspects of fitness.
With your background, you would take to it like a duck takes to water.
The window is definately NOT closed to progress. Just stick with it. Like I said earlier, you're still relatively young. You may not improve as quickly as an 18 or 19 year old, but you will definately improve.
For the jogging and sprinting, I'm not sure, but I would suspect you jumped into it too much too quickly. At least that's been my experience for sore shins. Again, check out crossfit. They have a lot of running and such, but they mainly do it with shorter to medium runs (400M-5K ususally, for time)Also, throw in some rowing or cycling for the runs if your shins are really hurting.
Good luck in your endeavors Mike. Good training