Ds in 10 and getting over a stinking cold.i left him upstairs having a shower. I went downstairs and heard a loud bump. Not unusual as ds is always hurling himself off bed etc, but called out and ran upstairs. Ds was sitting on landing looking a bit sheepish. I asked him what the noise was and he said she didn't know how how he fallen.He is not hurt but he said he had a pain in his head for a minute.I asked him what he remembered and it looked like he was suppressing a laugh but said he thinks he blacked out. He didn't look shaken or pale. Wondering if fluid in ears just made him a bit dizzy as can't see if he had properly blacked out how he wouldn't have hurt himself on banisters etc on way down. He seems fine now. Drs closed so don't know what to do.