When should I be concerned?

So I'm 39 weeks exactly and I've been up all night with decently heavy lower cramping that also radiates my lower back. This is my first kiddo so I'm kinda oblivious to what feelings to actually worry about. When I'm laying down it hurts to change position when they start. I'm very tired and walking around isn't fun right now. They don't seem very regular or close together, I haven't really been timing them since I didn't expect them to continue the whole dang night. Should I call my L&D? I can't really call my doc in my situation as I'm military and wasn't instructed to call him.