Thank you for your question.
I am Dr Saha, I shall try my best to help you.
This dose of advil or 800 mg of ibuprofen would not cause much side effect.
It can cause gastric irritation.
You can take antacid liquid to minimize it.
Diphenhydramine has been overdosed.
Maximum daily dose is usually 200 mg. which is divided in 4 doses.
It can cause drowsiness, dizziness.
I hope this information helps.
If there’s anything else I can do, please let me know.
If you are satisfied, please rate my answer as good or excellent.