I did go down the 111 route, got given a walk in Centre to call, they never called me back, as i was 22 in the queue at the time and you could set up a call back when you get closer to number 1. I gave up, plodded on, thankfully it subsided after a few weeks, since then i've had my annual review and i have my 6month hospital appointment next week. I did learn via bloods that i have low sodium, that would possibly explain the cramps, i would also be prone to foot cramps **eye roll** one thing after another.
I couldn't weight bare on my left leg from sitting to standing, once i was up and about it was fine, that moment i stopped and sat down, then started all over again. I'm fine now though, that's why i was curious what the OP had, if you google thigh pain, you get told, sprain, strain, injury.