<s>[INST] I tore or strained my hamstring and the pain has been so severe that I nearly passed out a few time. My leg swelled up hugh and is black and blue. It has been 1 week and the swelling is going down but the pain is still severe even on the surface of my skin. What sould I do. [/INST] Hi, Hamstring sprain will take about 3/4 weeks to heal(grade 1/2/3). You need to be patient. Till then need to avoid the movement of hamstring to aid in repair(avoid knee extension)You can were a knee support or crape bandage for stability. Kinesiotaping will help in this. Also use of contrast bath (hot and cold packs alternatively) will help in pain reduction Can take acetaminophen twice a day for pain relief. Hope this helps. Let me know if I can assist you further. </s>