That is nothing to worry about other than to look for a possible triggering activity. Headaches can be totally random so there is not always a trigger. But, dizziness tends to be tied to a trigger, at least in my experience. Dizziness can also be entirely anxiety.

As Bud says, Don't look for symptoms. Just be aware enough to notice, "I read that line 3 times, maybe I need to take a break."

And, if you break your streak of good days, don't fret, That streak of good days was still good for your brain. You did not negate its value. Don't keep count....