Thank you for the link to the other thread! Reading through some of that, it seems like it might be 'chronic compartment syndrome'. I think I will continue to rest it and if the pain comes back again, go and see a specialist. I've started a training log to make sure my programming is public and hopefully not stupid.
I am thinking that I will do some isolation work of the soleus (seated calf raises with a light weight) 2 times a week for a few weeks, and if that doesn't aggravate it, gradually reintroduce squatting starting with air squats and building up slowly. Or should I just rest it completely and leave it for a month, before starting something like the above, making sure that I stretch, heat, self-massage and foam roll it regardless of what I do?
Steven, here is an image showing where the pain typically is.
The pain is typically above and below where the soleus line meets the picture on the right.
I don't think it is a muscle strain because there was no sharp onset of pain. It's something that gradually builds up, both during the workout, and through a cycle if I keep repeating movements that aggravate it.