I Had An Upper Endoscopy Done Yesterday And My Bottom

I had an upper Endoscopy done yesterday and my bottom lip seems to be numb. I did call the doctor's office yesterday and all she told me that might be where the bite guard was resting in my mouth. It is still numb today and I was just wondering how long this goes for, and if this is normal? Thank you for taking the time to read this, I sincerely appreciate it.