Hello Slaven, I had something vaguely similar at the back end of last year, although it sounds like yours might be a little more serious, so wouldn't take what I say as gospel....

I basically overstrained mine from a massive increase in mileage and racing distance, and it gave up on me half way through the Roaches race.

I basically didn't run for a number of weeks, but I still trained almost every day, either cross trainer or cycling, but nothing too stressful. As mr bright side says, stretch it every day. Then every week or so I tried an easy run and if there was any strain at all I gave it another 5 days away from running.

Eventually back to full strength and it's been fine since. I suspect yours is more problematic if you have gone 7 weeks. But just ensure it isn't stiffness and soreness from not training.