Aggravated calf

I’ve never had any problem with my calves and getting to a doctor might be a little difficult for the time being…so…here I am, I hope someone might be able to offer a little advice. I’m 20, in fairly decent shape, and am having some problems with my left calf muscle. It’s been aching and slightly inflamed for the last 2.5 weeks at least. I’ve been trying to stay off of it as best I can but it has been difficult as I don’t have a car and use a bike to get around. The ache originates behind my leg in the thickest part of my calf about 4 to 6 inches below the knee joint. It doesn’t bother me when I sit, only when walking or biking. 600 mg of Ibuprofin seems knock it back a bit, and I’ve been icing it, but it hasn’t gone away completely. Any ideas on just what I’ve managed to screw up?