Since you seem to be offline, ill leave a response here which we can discuss later on.
The first thing which comes to mind after hearing about your symptoms is that you could have compression of the nerves in the lower back which is causing the pain in the buttocks. This would lead to the pain which you have as well as other symptoms like tingling, burning as well as numbness in the lower legs. However it is not necessary for other symptoms to be present. The diagnosis is made with a clinical examination, xray of the back as well as MRI of the back. The treatment can be with painkillers, steroid injections and also with physiotherapy.
Another cause of this would be related to simple muscle spasms. Muscle spasms can occur due to various causes however the two most commonest by far are dehydration and electrolyte imbalance. This can also cause pain when you sit down. Now the best thing to do here would be to increase intake of water and at the same time increase intake of electrolyte rich fluids like gatorade. In addition painkillers like motrin or aleve would be useful as well.
Lastly this can also be due to sacroilitis. This is inflammation of the sacroiliac joint in the back and buttock region. This would be diagnosed on a xray of the back and pelvis and then treated with painkillers as well as steroids.
For now i would suggest that you start using OTC anti inflammatory agents like motrin or aleve and at the same time increase your fluid intake. If the symptoms dont improve in the next 72 hours then contact your doctor for further testing.
Do you have any more questions?
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