Hi You seem to have had a muscular strain while you were picking up something heavy. It typically causes sudden pain with sometimes a pop sound or feeling while the patient lifts up weight. When the pain is strong sometimes the patient might also feel dizzy due to it. To help with the pain you will need to avoid other weight lifting or exercises but use Ibuprofen every 6 hours after food (to protect the stomach) and combine it with paracetamol every 6 hours at the same time. The first couple of days cold compresses may help alleviate the pain but later you can try warm compresses locally. Please don t massage the area as this may make the hemorrhage in the area worse and pain worse as well. You may benefit a lot by seeing a physiotherapist which can examine and identify the hurt muscle and give you exercises to help it relax and also strengthen it. Hope I have answered your query. Let me know if I can assist you further.