I suggest talking to your primary care doctor
as a first stop.
Sometimes having numbness
(pins and needles) in the feet after prolonged sitting can be a problem if you are putting pressure on the nerves in your legs and causing them to 'go to sleep.' You should make sure that you are working in a seat that is ergonomic and properly positioned to try to avoid this.
The swelling is a bit more unusual because swelling should not be caused by pinching nerves in your legs. One possibility would be varicose veins
, which can cause swelling. Make sure you change positions frequency and get plenty of exercise as well as make sure you maintain a healthy weight can all help with this a bit.
I would, however, make sure to have a complete checkup from your primary care doctor. Other causes of numbness and tingling would include thyroid problems and other nutritional deficiencies, such as B vitamin deficiencies. Also, with any history of swelling in the legs, it is important to make sure there is not a more serious problem, such as a heart problem, going on no matter how unlikely. Your doctor will help you figure out what you should do.