Calling out sick

I woke up today out of it, after my alarm, and with a 103 fever….. one hour before my shift. I called ASAP knowing i definitely couldn’t come in. This is my first time calling out and it made me more sick to my stomach. My manager is pissed and said it might be an unexcused absence. What do I do from here? What happens? Am I in trouble, is there a written warning? I’ve never done any of this and I’m so anxious. I’m a great partner and I’m always at my shift 15 minutes early and I usually stay after. Help!