You can still have groin muscle strain, which is what this sounds like
Even from sitting to long then suddenly standing.
Rest, stretching and ibuprofen if needed are the treatment, initially, physical therapy would be idea;
you should also make sure, from doctor exam, that there is no hernia, and there does not have to be a bulge, and that there is no hip problem, and hip pain refers to groin.
So....does not sound serious...but needs exam.
Let me know if you have further questions, details or need clarification, just use reply.......
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