After an intense cross fit workout, I accidentally fell on the floor on my head. It didn't hurt much physically but after a while when I stood up and sat with head down, a yellowish watery discharge started coming out of my left nostril for around 2-4 sec and it stopped. I got panicked and rushed to my home. Didn't do any workout for two days. On third day, a similar colored thick discharge came in a sneeze after workout. No such sign on day 4. Is it a serious problem or just a temporary issue? I don't feel fatigued or light headed. No sort of light sensitivity and all my cognitive senses are working fine.