Pins and needles-esque feeling in leg all day

For about 6 or 7 hours now my leg has had this uncomfortable feeling like pins and needles but its slightly painful and is most persistent right above my knee. It's only on my right leg. I've had it a few times before when I've been asleep and its woken me up in the middle of the night. That only happened maybe 3 times and it only lasts a few minutes. That probably is just regular pins and needles as 2 of those times i was cuddling someone.

I should also mention I'm an 18yr old female and i take nitrofurantoin (100mg once a day) for recurrent UTIs and kidney infections. I'm 166cm and 67kg but ive gained 7kg january (around the time i got a personal trainer) without a huge change in my appearance so don't take that to mean im overweight (for my self esteem).

It's such a frustrating uncomfortable feeling which comes and goes and when i ignore it goes away but its difficult to ignore. i've walked a normal amount today but recently ive been sitting in bed a lot as its where i revise for exams.

Its such a horrible feeling. Should i be concerned and how do i make it go away?