If you're in the USA, your only choices are: Tramadol, Codeine, Tapentadol, Morphine, Hydrocodone, Oxycodone, Hydromorphone, Oxymorphone, and Fentanyl; strength is in order from weakest to strongest (that doesn't mean that the weakest won't work as you have to build up a tolerance to medication and all medications act differently.
The above listed medications are known as narcotic opioid/opiate-based pain killers and are highly addictive with withdrawal symptoms if you choose to suddenly stop taking them.
Your question was very vague. Is your pain muscle, neuro, or bone-related? If more than one is associated with your pain, then you'll need a combination of medications to help alleviate your pain.
Common neuro pain relievers: Neurontin, Lyrica
Common muscle relaxers (for muscle pain/spasms): Flexeril, Zanaflex, Baclofen, Soma
It's always best to try over the counter medications instead of getting prescriptions, especially mentally addictive and physically dependent medications as listed above.
In some countries, such as Canada, Mexico, and across the UK, there are over the counter pain relief medications. Some provide combinations of weak opiate/narcotic medications while others contain combinations of muscle relaxers. It must be so nice to live in such free open market countries so that you can find what's best for you.
Common over the counter medications: Tylenol, Ibuprofen, Alleve, and Aspirin.
Again, you were vague and don't say anything about your pain or what's causing it. Maybe you strained a muscle and thus that could be healed within 3 days with proper care without any medication.
Good luck to you.