Vomiting post insulin shot

Hi all. I quite literally found out that my 10 year old Chihuahua has diabetes less than 3 hours ago. It was very overwhelming to get the diagnosis and receive all the instructions, and I feel very out of my depth.

She received her very first insulin injection of 1.6 units of Vesulin at around 7:15 this evening. She eat a can of dog food that the vet provided to me. I briefly stepped out of my house to get dinner, and at about 8:15 she vomited a bunch. I only know because I watched her on the Ring camera.

She refused to eat but I was able to liquify a little food and give it to her through a syringe. I’m seeing conflicting information online, and since my vet is closed, I’m freaking out, especially because you may not see the side effects until hours later. Should i try to give her more food or leave her be? She’s sleeping now and is otherwise fine. This is all just extremely new and I’m scared 🙁 Any help appreciated