Today, I Was Hanging Upside Down On A Bar. My

Today, I was hanging upside down on a bar. My friend accidentally kicked ky head, but ir was a soft kick. My nose started to bleed and my vision became woozy for about 10 - 15 seconds. I then walked to the bathroom to clean the blood when I fell onto the toilet from dizziness/clumsiness. What's wrong with my head? I was also a bit behind for about 30 mins.