Finally got over the calf strain in my left leg and was running again and now my right one is strained. Same part of the calf as the left one (soleus). Pain was gone after a few days of R.I.C.E., but I'm being extra cautious with it. My left one didn't start out serious either, but kept getting re-injured after I thought it was healed. Ended up lingering for months.
The worst thing about these strains is there's no warning at all. I stretched before this last injury and was feeling good during the run and then it just seized up.