Sounds like leg cramps to me - I've got the same thing, its like nerve pain, like you might not be getting enough blood to your legs. I thought about the blood clot thing too, especially as my Mum had varicose veins when she was younger.

My doctor told me to increase my calcium and magnesium - I think it tends to be a lack of salts that causes the problems - But I'd just give your ob a call and check, they will let you know the best plan of attack.

And my ob said taking panadol for the pain was no problem at all.