Pain in calves at night

I run approx. 3-5miles 5 times a week. For the past 3 months I have been experiencing pain in my calves when I lay down. The pain is an aching and there are muscles twitches in my calves. I am relatively pain free when I run except sometimes my calves are very tight and don’t seem to loosen. The pain at night can be so severe that it wakes me up or prevents me from sleeping. I went to a family Dr. and she mention compartment syndrome, but said that I probabaly don’t have it since I don’t have a lot of pain while running. Any ideas?
Thanks for you input!