Thanks for the additional information,

there are a number of conditions which can cause this problem of yours and ill enumerate the two most commonest ones of them which should be looked into,

the first one is as you rightly surmised a problem with your circulation. ALthough the major symptom in a patient with peripheral vascular disease that is a disease in which there is an obstruction of blood flow in the legs is that of pain while walking, it can sometimes present with these vague symptoms and it is important to rule this condition out first of all. Now the first thing which should be done in such a case is the following,

A clinical exam focussing on the vascular system, that is chekcing teh peripheral pulses etc.
Doppler ultrasound of the legs
A fasting lipid profile

After these test are done then we can deciude whether you should be treated medically or surgically with the implantation of a stent.

Next condition which can present in this manner is basically the compression of nerves at the spine or at some point through the passage of the leg. This can cause pain in the legs even below the knee joint alongwith numbness. This is basically due to the compression caused a prolapsed disc or even some constriction caused in the buttock region by fibrous tissue. This can again be diagnosed with the help of a clinical exam and a MRI of the back if needed. treatment is with painkillers and/or surgery.

Lastly this can be peripheral neuropathy but i doubt this is the case because neuropathy is usually symmetrical which means both the legs are affected and you dont have any of the risk factors for neuropathy. So your best bet is to look into the above two conditions and see what happens after a clinical exam.

i hope this helps