Accidentally gave 4 month old 3 Oz of water??

I've been exhausted all week because I've started work and my 4 month old has a cold. It's currently 4 am and I was half asleep and my little girl woke up hungry after 4 hours of sleeping. I don't remember even sitting down with the bottle and taking my baby girl from my husband. But I began to feed her and I fell back asleep as she was drinking milk. I lift her bottle and I realize that I hadn't put her milk powder in her bottle and I had just unknowingly fed my baby girl 3 Oz of water. There was 1 Oz of water left as she drinks 4 ounces of milk. I freaked out and Google it because I'm a ftm and I freak out about everything and that made it worse. It's saying that my baby could die or go into a coma from water intoxication.

It was an accident. I quickly tried making her throw up and that didn't work it wasn't coming up. So then my husband just said to feed her the rest of the 1 Oz and add her milk powder to it.

She seems fine and fell back asleep. She's breathing fine but I'm freaking out. I've cried my eyes out and I don't know what to do. What if I seriously just harmed my baby?

I can't sleep and I'm making her sleep in my bed with me. (normally she sleeps in her bed) What do I do?