I think I had the same thing a few years ago. Bursitis, I thought it was.
I'm not sure what it was this time around, but whatever it was it wouldn't let me sleep at night. Could be it was the result of all too hard a bunk bed on the cruise to Turku, could be it was the very basic (also not soft) beds at the Chesscom Guesthouse earlier, but it could also be I've just somehow moved my hips in unnatural ways while I've walked, or put pressure on them the wrong way whilst lifting weights, or possibly just slept wrong.
I usually sleep on my side, my right side, but the past couple of weeks there have been nights where I haven't been able to sleep at all. Lying on my sides didn't work, lying on my stomach definitely didn't work (I realized after posting that this particular way of phrasing this might give the impression I'm fat - I'm not - it's just uncomfortable), but at the worst times just lying on my back didn't seem to work either. It felt like my leg wasn't attached to the rest of my body, like it was stretched out, like - I imagine - on the torture racks you see in old torture chambers.
I tried adding pillows, a sheepskin patch, and eventually a softer mattress, and taking arnica (wolf's bane, great for bruises), and essential oils, and finally it seems to be alright again. I can't move my leg carelessly or I'll get a jolt of pain, but I can sleep! And walk. And I can sit around doing nothing - which oddly enough was always the one position where the hip felt OK.
Do wonder what it is though, and what sparks it, and how to best prevent it from ever coming back - because it really ain't pleasant. For now I'm stretching, and sleeping on my back a bit more than I used to.
Somehow that just doesn't feel like a sleeping position. I'm not sure I ever slept on my back before these two weeks, but when you're just tired enough any position works okay.
So, don't be a hipstir now. Here's hoping the new week's left me all cured! Oh and my cold: it's pretty much gone. Hopefully the final traces fade away through the night too, and the new week starts alright/new.