So I got dizzy and blacked out and hit my head. I've got a bump on my forehead, feeling ok other than a headache and a bit of dizzyness still. Called into work mainly because I didn't think it was safe to drive right now. I put ice on it and am drinking some water as I think it happened because I was dehydrated. My problem is now I don't know when you absolutely should go to the ER and when it's not absolutely necessary. I'm leaning towards not going, but I don't really know. Any suggestions? Anyone know when you should definitely go to the ER or if it sounds like a sit and wait type thing?