This sounds like sciatica to me. You can treat this with NSAIDS, stretching exercises (YouTube has many videos of physical therapy exercises for sciatica), and heat alternated with ice. Steroids would be the best course of action if you are able to save money for a doctor's visit. Bed rest is not advisable and can make it worse. If the pain becomes unbearable, you have swelling and redness, you begin running fever, become short of breath, or you have any concern for a DVT, you should seek emergency care. You will incur an ER fee for services, but they cannot deny you care. If you don't have money upfront, they will still treat you. I hope you feel better soon!
Sorry you are hurting. So, no injury preceded this? Pain can change where we are having it as we sometimes will compensate for pain that starts in a hip. We'll walk different and then that will in turn make a knee hurt and so on. Anyway, this has been going on for a few days? Things to try . . . ibuprofen. That's the only pain reliever I'd take now. If there is swelling in the joints too, ibuprofen will decrease that. Stretching. Can you do any stretches? Stretching can help but make it gentle. You can elevate it and ice it. But overall, the best thing is to see your doctor. I don't know if you have an injury of some sort that they will need to address but they can examine you and find out. By the way, are you in any way overweight? Just curious as that can compound things. Let us know what the doctor says!