What Causes Nasal Congestion After A Head Injury?

Hello, about 3 weeks ago I was snowboarding and fell and hit my head and I believe I only lost consciousness for a few seconds if at all. My headaches and such went away and I feel fine but sometimes here and there I get a headache. I also was congested a few days ago and now my nose doesn t feel very stuffed up or anything but when I was playing basketball tonight my ears sort of felt like they were full or had a little water in them. I m not sure if that had anything to do with my head injury or not but I read online that the feeling in my ears could mean a lack of oxygen to my brain. The feeling went away shortly after I was done but I m just wanting to make sure it s not related to my injury if it s only when I was running but sometimes depending on how I have my head they kind of feel like that again. Is this likely from sinuses even if I don t have facial pain or a very stuffy nose or could it be from my injury even though I have felt fine since then for the most part. The headaches I have had have not been in the same spots either. I ve also had some green stool lately so I m not sure if that helps with anything or not. Thank you!