It looks like you are anaemic. If you have back pain
after you sit for long hours then it is due to your haemoglobin levels as it is important to check that. Anaemia always leads to the symptoms of being tired and also having back / leg pain
though there may not be any pathological reasons for back pain. Exercises
•Standing hamstring stretch: Place the heel of your injured leg on a stool about 15 inches high. Keep your knee straight. Lean forward, bending at the hips until you feel a mild stretch in the back of your thigh. Make sure you do not roll your shoulders and bend at the waist when doing this or you will stretch your lower back instead of your leg. Hold the stretch for 15 to 30 seconds. Repeat 3 times.
•Cat and camel: Get down on your hands and knees. Let your stomach sag, allowing your back to curve downward. Hold this position for 5 seconds. Then arch
your back and hold for 5 seconds. Do 3 sets of 10.
•Quadruped arm/leg raise: Get down on your hands and knees. Tighten your abdominal muscles to stiffen your spine. While keeping your abdominals tight, raise one arm and the opposite leg away from you. Hold this position for 5 seconds. Lower your arm and leg slowly and alternate sides. Do this 10 times on each side.
•Pelvic tilt: Lie on your back with your knees bent and your feet flat on the floor. Tighten your abdominal muscles and push your lower back into the floor. Hold this position for 5 seconds, then relax. Do 3 sets of 10.
•Partial curl: Lie on your back with your knees bent and your feet flat on the floor. Tighten your stomach muscles. Tuck your chin to your chest. With your hands stretched out in front of you, curl your upper body forward until your shoulders clear the floor. Hold this position for 3 seconds. Don't hold your breath
. It helps to breathe out as you lift your shoulders up. Relax. Repeat 10 times. Build to 3 sets of 10. To challenge yourself, clasp your hands behind your head and keep your elbows out to the side.
•Gluteal stretch: Lying on your back with both knees bent, rest the ankle of one leg over the knee of your other leg. Grasp the thigh of the bottom leg and pull that knee toward your chest. You will feel a stretch along the buttocks and possibly along the outside of your hip
on the top leg. Hold this for 15 to 30 seconds. Repeat 3 times.
•Extension exercise: Lie face down on the floor for 5 minutes. If this hurts too much, lie face down with a pillow under your stomach. This should relieve your leg or back pain. When you can lie on your stomach for 5 minutes without a pillow, then you can continue with the rest of this exercise.