aye, this morning my legs ached like hell so I didn't go out, will try to tomorrow to balance it out. How many weeks in should I look to add distance onto my 4k ish loop?
Aim to add no more than 10% of your total weekly milage each week. So say you are running 4km, 3x a week, thats 12km. You can increase this up to 10% so 1.2km. So the week following this example your total milage would be 13.2km. I avoid silly numbers like this, or round to the nearest half km, in this case I'd do 13km. Then the following week, probly more like 13.5km, total weekly milage, and so on.
With a sport specific injury, if you can afford it, its best to go see a sports injury clinic, because they understand you, your aims and likely they are familiar with similar injuries. A GP may or may not know a whole lot regarding your injury and will just suggest "if it hurts when running, dont run".