Physiotherapist
It's bit unusual for someone to advise such quick return to activities, when you consider muscle takes around 6 weeks to heal, and additional time and treatment required to bring the state of muscle back to normal function. I would suggest minimum activities for now and use of crutches so that minimum pain is perceived when you walk. You will need to be re-assessed to determine what's the cause of this pain, could be nothing major or something sinister, ie like further damage to muscle as you suggested.
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