I think your mum is experiencing state of the art panic attacks which feed on themselves as we know all too well!
Ask her to learn some relaxation exercises: sitting in a comfortable chair with hands in the lap, breath in sharply through the mouth, hold for the count of 3, then let out through the nose as slowly as possible. 3 times. Have a buzz word ……. 'relax', 'sunshine' ….
Sitting in a comfy chair, hands in lap - eyes shut, then starting from the toes - tense, relax - through all the muscle groups. Concentrating on the muscle groups calms the body. Practicing 3 times a day is important as well as in bed if she can't sleep.
Soothing music ……… again in the chair, sitting quietly - tuning the brain into the upper line of the song/tune, or the bass if it's male singers, anything to concentrate the mind.
The tingling is probably an adrenaline surge. For me it's like hot water running through my veins

scared the pants of me the first time ….. not a pleasant sensation but does dissipate eventually.
When do you see her again?