It s been around 40 hours now, since I banged the side of my head. (banged heads with someone else by accident) aha, It feels bruised near the area, as it would. And there is a small lump. I haven t experienced any headaches . Anyway, I was drinking at the time, and I had quite a bit too drink. Anyway, since then.. I have felt quite dizzy, and light headed. It was worse yesterday, and today it doesn t seem as bad. But, I don t know whether the dizziness has got anything to do with the alcohol (hangover) or concussion maybe? Should I keep an eye on it? Or do you think it s plainly just down to the alcohol. And if I did have concussion, would I know about it by now? almost 2 days.