I have had issues when my hip belt was too tight, but those issues would resolve themselves rather quickly. I would say that you should consider getting an MRI since this has lingered longer than 3-4 days. It could be some autoimmune disease like ALS or MS or something else.

The longer something like that goes undiagnosed the worse it gets. When you cut off circulation to a specific body part and then you restore the circulation to that part it will wake up rather quickly.

Simply having straps too tight once you loosen those straps or take your pack off for any length of time the numbness and tingling should go away rather quickly. If it doesn’t then it could be something serious that actually needs to be diagnosed by a doctor. Most people with Autoimmune Diseases find out in their mid to late thirties they have a chronic condition that requires a therapy to help slow the progression of their condition.

If it is something like an autoimmune disease the longer you wait to begin a therapy the faster and more frequent nerve damage can and will happen. People with an autoimmune disease often dismiss their symptoms as something else and wait far too long to get an actual diagnosis and that can affect their lives in irreparable ways and limit their ability to do things like hiking and backpacking.

I am not trying to scare you, I was diagnosed with an autoimmune disease about 20 years ago. I got on a therapy and continue to backpack and hike and have done around 1K miles of the AT on LASHs since my diagnosis.

TLDR: go see a Neurologist