Perhaps the hit on the head is the key.
I remember one case in college when I hit my head in the morning and got a minor concussion, yet I stubbornly decided to go to classes regardless of it.
That same day we watched a few videos in one of the classes, and I remember that I felt pain and slight disorientation every time the lights were turned on. After that, the mere thought of going to another class made me feel very sick, so I just went back to the dorm and fell asleep (even though it was only early afternoon).
So, a strong bump to the head combined with your other issues could be the cause for the difficulties you experience. If this is the case, then things should go back to normal in a few days.
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