Do I have a mild case of dyslexia?

There is a lot more to dyslexia than slowed reading speed.

Check this out:

http://www.dyslexia.com/library/symptoms.htm

This does not sound like dyslexia, it sounds more like the inability to concentrate or process what you have just read. Are you reading for school or pleasure?

You may be trying to read to fast, in order to save time for other things. I used to do this in my college years and I would literally read 4 paragraphs and then have to re-read them again, having no idea what i just read.

Attention deficit disorder may also cause such symptoms. (a very mild case that could be caused by stress or recent lifestyle changes)

People process what they read differently, and sometimes an individual will process differently on different occasions.

My husband read slowly, much slower than I do, but he grasped what he read relatively permanently - in my observation, information got processed in his mind more deeply - and he could put together the basics of any book or movie years later.
I read fast, and have memories of great word strings, word sounds, word rhythms, clever nuances, bits of wit, visual associations from descriptions, and the odd point of view or two... much as a bath of words with interludes of my being in the room with the characters, then looking for the next 'ride' of words. I'll tend to remember who directed the movie, perhaps who wrote it, who the cinematographer was, and fail to be able to recount the storyline with any precision. I don't consider either of our ways of reading a failure, as such.

Does your concentration vary? Perhaps your concentration relates to your underlying interest level?

I'm not sure what I think about that website - it seems to list far too many quirks. If it's accurate, I surely am dyslexic (which wouldn't be surprising to me).