Thanks for the details.
This seems to be a muscle strain of the pelvic muscles. Whenever you lift something heavy the pelvic muscles contract and come under stress and strain. This happens especially when you lift something very heavy.
Starting motrin is good idea, I hope you are on the right dose, Motrin 600 mg thrice daily.
Hot baths and hot compresses on the area that hurts.
No vigorous activity or weight lifting for at least a week or till the symptoms subsides.
You should see the doctor if the fever continues. However, an ultrasound (regular or endoscopic) will reveal if there is a hematoma in the area of the pelvic floor that sometimes develops as a result of muscle rupture or strain.
You should start on a high fiber diet and bulk forming agents like psyllium husk (metamucil) 2 table spoons thrice daily or Benefiber sachets thrice daily. Constipation promotes straining on the pelvic muscles which can make this condition worse.
If the symptoms do not subside with the anti inflammatory in another day, a physical examination by a physician will be necessary to rule out other conditions.
Hope this helps.
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