I fell down the stairs and am worried. What happened?

I went downstairs to get tissues cuz my nose was really congested and when i went to the stairs I felt like I lost control of my legs and I ended up sliding down the stairs and when I got to the bottom, I regained control or something and the whole thing was a blur. What the hell happened? prior I was playing video games in bed and I've had a cold for the past few days. I'm 16