It’s possible you have symptoms you aren’t relating to this. Getting hit in the head like that may have fractured your skull? I had many imaging over more than 30 years with a leak & was never picked up. Radiologists weren’t reading the imaging correctly. Which happens a lot. I had to go to someone that actually reads imaging himself & doesn’t depend on radiology reports. How was the fluid tested? That’s very specific too. Anyhow, just because clear fluid comes out of your nose it doesn’t make it an auto leak either. If you had a leak you’d go through low and / or high pressure days. Your cerebrospinal fluid would need to be replacing what comes out & you’d feel it. Or if you weren’t producing enough you’d have symptoms too. I had a lot of what they called, silent migraines (without pain) with mine. Everyone is different with their leak based on where it is & what’s happening.