Brief Answer:
Suggestive of Sciatica (pinched nerve)

Detailed Answer:

Dear Madam,
Thanks for posting your query on HCM.
I appreciate your concern for the radiating leg pain.

The typical symptom described is suggestive of sciatica.

Sciatica is caused by irritation of the nerve roots in the lumbosacral spine.
Other common causes include:

Narrowing of the spinal canal in the lower back (lumbar spinal stenosis).
Breakdown of discs, which act as cushions between the vertebrae (degenerative disease of the disc) or a condition in which one vertebra slips forward over another one (spondylolisthesis).

You need to be examined by a doctor preferably a neurosurgeon for further evaluation and relevant investigations ( X rays of the spine & MRI) to confirm the diagnosis.
Meanwhile take some NSAID pain killers Aspirin with PPI to prevent the acidity related stomach upset, avoid lifting heavy objects, bed rest, avoid sleeping on a mattress that is too soft.

Hope the suggestions given above could be useful in getting the treatment from a neurosurgeon.

Best regards.

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Brief Answer:
There is a possibility of shingles

Detailed Answer:

Dear Madam,
Welcome back to HCM.

Since you have informed just now that you have burning sensation and a insect bite like rash, It is suggestive of shingles

Apply cold wet compresses to the rash to reduce pain
Applying calamine lotion to reduce itching
Take NSAID pain killer like Asprin as advised earlier

You may have to take Anti viral drugs like Acyclovir for that you may have to visit a doctor. And if the pain does not subside may be you need to take Amitryptiline or Carbamazepine.

Hope this answers your query.

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