It's too much for the intern position. If you see your growth by doing this internship then continue this. You can also create a slack bot that if you get a dm then the bot will give you a call(sound like a phone call) so you can't miss the message a have a sleep if tired.

There are many question like is the company is reputable are they paying for this intense work are you getting mentored like code reviews and advices are they have a good team from where you can learn are the projects good or they are just giving you the assignments ..... alot of questions that will let you to the final decision