You may have a sore neck and upper back with pressure behind your eyes because of leaning over a desk for prolonged periods without exercising your neck and upper back. When you lean your head over your desk then you compress the veins, arteries, and nerves in your neck. The veins send blood back to your heart and they lead from your eyes through your neck to your heart. So that if you lean over a desk for prolonged periods then you'll constrict these veins and this causes the pressure to build up behind your eyes. The arteries from your heart pass through your neck and contain blood with oxygen so that if the arteries are compressed because of bending your neck while working at a desk, then your brain receives less oxygen and this will cause you to feel dizzy and lightheaded. You should take a break every hour. Get up from your desk and walk around. Do some toe-touches and upper back and neck stretches every hour.

You've had an ultrasound and you've been examined by your doctor already so I would assume that he's ruled out kidney stones. So that your mild cramp-like pains in your lower abdomen are most likely due to diverticular disease (also called diverticulosis). The most common symptoms of diverticular disease include abdominal cramping which is related to difficulty of passing stool along the left colon narrowed by diverticular disease. Diverticular disease can be caused by chronic constipation which makes the intestinal muscles strain to move stool that is too hard. Constipation is the main cause of increased pressure in the colon which can cause weak spots in the lining of the colon to bulge out and become diverticula. A desk job and/or a sedentary lifestyle can cause your intestines to have decreased motility and this can lead to constipation and cramp-like lower abdominal pains. You should exercise more often which includes toe-touching, twist your abdominal muscles, bend from side to side, and stretch. A heating pad on your abdomen can help to increase the circulation to your intestines. promote intestinal motility, and reduce cramps. Avoid foods that contain indigestible particles e.g. nuts and small seeds. Drink at least 2 quarts of liquids a day to prevent constipation. Take 30 cc of milk of magnesia before bed so you will have a normal bowel movement in the morning. This should relieve your cramp-like pains.