Hello,
I have been diagnosed with ALS. Tingling is not a sign or symptom of ALS. ALS only affects the motor neurons so there is no pain, no loss of senses, no other sensations. ALS symptoms are: a loss of movement and range, loss of muscle, and muscle twitching.
I am not a doctor but I would tell you, "Don't worry, its not ALS".
To me your symptoms look like a pinched nerve around the sacrum and lumbar spine. A kinesiologist would help you with that.
But, the worst case to leg tingling could be MS. Get an MRI on your brain to find out.
Good Luck to you.
What is your vitamin B12 result?