I am Dr. Thomas, board certified in internal medicine and integrative medicine and I can help you with this and any follow up questions. I cover a lot of ground and might give you an answer or ask for information, but use reply to communicate with me for questions or added details.
You do not have a diagnosis.
Given that you were twisting and playing tennis and felt a "pop" this can be more than simple strain.
A slipped disc must be ruled out, torn ligament of the spine is possible, and you need a structural exam.
If indicated by exam you need an MRI.Simply treating it at home without follow up is not adequate and potentially leaves you open to long term complications...for example you might need the correct physical therapy.
Do not simply treat this yourself and assume everything will be fine.
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