Problem when ever I run with my shins, calves and knees

OK, having a bit of a nightmare at the moment.

I'm currently in training for the army and I've started having really bad cramps around my shins and on my knees when ever I run. Its absolutely fine if i'm walking or carrying weight, but the moment I run I start to have issues and I've no idea why. I have the option of going sick so I can see the physio on camp but that means I'd miss out on loads of training. I've ruled out the idea of going to see a normal physio because by the time i'm done for the day and alowed to leave camp, most are closed anyway.

The problem starts about a minute into running and i start to feel a sharp cramp like pain in my lower legs around my shins. As soon as I stop and begin walking, or even standing still, the cramps get more painful and make my legs buckle slightly and shake. The pain spreads up to my knees and around my calves untill it feels like the whole leg is under horrific amounts of strain and stress. the pain usually hangs around aswell, usually subsiding about half an hour after the physical activity.

Does this sound familiar to anyone here? Do you know how to fix this problem, or even how to go about preventing it? I desperatly want to avoid sick parade because I will have many of my priviledges takes from me.

Any tips, help or advice would be greatly appriciated.

Thanks