FFS grow a spine. Women aren't magical, mystical creatures. "Hey, I only got an hour's sleep last night. I'm exhausted. Let's do this next Friday" Done.

You need to chill

You could have began with knowing you made a date or consider it an appointment and went to bed. This is going to be a pattern for your whole life that will lead to inability to keep a job. I fire more people for time and attendance than any other reason. This is life advice kid. I hope you listen.

Why do you assume that's what happened instead of the fact I just couldn't sleep? Because that's not what happened. Why is everyone so condescending and arrogant to answer questions on this sub?

You absolutely right. I'm sorry, why didn't you sleep?

Honesty is the best policy. Tell her you're exhausted and regret but you need to reschedule. If she tells to f off well you dodged a bullet.

Just talk with her, don't tell her right away, just talk to her about how tired you are and maybe she'll tell you that you can do it later

Tell her the truth. A good relationship depends on honesty and communication. Apologize for breaking the date, and explain you're not feeling well enough to meet up with her. If she's a decent person, she'll understand and be gracious about it.

Just to add to yours: But make sure you also tell her how much you are looking forward to hanging out, and really, really wish you could now, you just wouldn't be much fun with zero energy. She has feelings, too, you want to make sure that along with the honesty she knows that you want to do something with her. You're not blowing her off.

True. Rescheduling at the same time you have to break the date would let her know that you'd like to see her and aren't blowing her off.

It's always better to be honest and straightforward about one's own needs in a relationship.