Lethargic and Won't Eat

Hi everyone! I'm new here, but found this place by googling, and after reading a few threads and seeing how caring and loving and nice you all are, I thought I'd share my concern.
(Sorry if this has already been posted, I went a ways back and didn't find anything with this exact scenario)

My little girl, Betty White, is about a year and a half. She's an indoor only cat who is constantly running around and talking and playing with everything. This morning her and her older sister woke me up at the normal 5am breakfast time and both ate. At about 9 this morning I strolled out of the bedroom to find Betty had just coughed up a hairball, and there were 2 other little puddles of light brown bile next to them. I cleaned them up, she seemed normal. Over the next hour though, she threw up (just liquid, light brown/clear bile) 4 more times. And about 10 minutes after she started acting like she wanted to sleep but couldn't get comfortable.
My husband said I was being paranoid. When we left to go d errands, she was asleep in her favorite spot, didn't think it was anything to worry about. When we got back a few hours later, she hadn't moved from the spot. We picked her up and tried to play with her, she wouldn't even look at her favorite toy. I tried her favorite treats and she didn't even raise her head.
Finally I called the vet, and they said I should take her to the emergency clinic. Which we did.
She meows the entire way to the doctors, which was normal, so that was good. She was lively and active at the hospital, but the doc said it was probably adrenalin.
She wasn't running a temp, they said her stomach felt normal and she hadn't thrown up for 8 hours. But she was a little dehydrated.
They didn't know what to do. He said because she's so young, it could be that she's just feeling icky because she's trying to pass a hairball, or it could be something more serious. The suggested 2 options. The first, they could do blood work and X-rays and see what they find - that was going to cost $1000. Or we could have them give her an antacid and something for the nausea and a shot to help with the dehydration. For $300

We went with the $300 option because we don't just have $1000 laying around.

We've been home for about 5 hours. When we got home she seemed a little better. She walked around a bit, rubbed up against stuff like she used to. Still no eating or drinking. And she's pretty much been sleeping the whole time. I think I'm going to take her to our vet in the morning, and see what she says.

So my questions are..
1. Should we have just bitten the bullet and paid the $1000 for the tests? We asked the vet what they suggested, he wasn't really any help though..

2. Am I stressing nothing and is it just a hairball thing that will pass? Neither of my girls have been sick like this before, so I'm not sure how well I'm going to sleep tonight.

Thanks for reading! Any feedback is appreciated!

I think if she don't get better by tomorrow, I'd take her back to the vets. Its so typical, that things like this happen during the weekend. On monday the tests should be cheaper as well

Hope your kitty feels better soon

Personally, I'd be thinking of taking her to your normal vet tomorrow - especially if she's still not eating. She will definitely be dehydrated from not eating and drinking, and going without food for as little as 48hrs puts her at risk of developing hepatic lipidosis (fatty liver disease). This is a serious condition that can be fatal.

It could be nothing major, but you do need to get fluids and nutrition into her and your vet is the best person to help you with that.

Hoping it's nothing serious and that she's back to her old self soon

Thank you both!! Yeah, I just woke up and watched her get up from her sleeping spot she was in last night and move to a shoe box she adopted yesterday morning. I don't think she got up at all in the few hours I was able to sleep. I just squirted a few syringes of water down her throat and force fed her a few nibbles of boiled chicken.

Thanks again!