Just my 2 cents again...
keep in mind that "all" of the symptoms do not need to fit each individual child...there are varying degrees of how everyone is affected by dyslexia or other learning differences.
We have had to come up to speed on this very quickly this past year with our 7 year old and we've done much reading and research. One thing that struck us as interesting (from reading and hearing from many friends) was that many times teachers take the wait and see approach...oh, he'll outgrow it or he's just immature for his age...fortunately, our son's was detected before he started to "fail" or get too far behind compared to his classmates. My number one concern is that my child "feel successful". Grades 1-3 are key for learning to read, after that, it is essentially "reading to learn"...science, social studies, etc. Many times by taking the wait and see approach, it won't be picked up until 3rd or 4th grade...by then, kids can be way behind and feel terrible about themselves.
Dyslexics are just "wired" differently and need more intensive instruction on phonemic awareness...breaking down words...recognizing sight words...and so on. You need a highly qualified tutor...spec. ed degree and trained in reading instruction.
Also, keep in mind that there are many great teachers...unfortunately, they cannot be experts on everything and may not know much about dyslexia or its symptoms.
You may want to compare what testing was already conducted by your school for your son to tests recommended for picking up on dyslexia...SchwabLearning and Sally Shaywitz's book would probably have the info. In our case, he seemed fine on initial testing...by the grace of god, the tester picked up on subtle things and tested further....bingo! Then seeing all the results, we could connect many dots.
Anyway, I'll get off my soapbox...just something I am passionate about and we have been fortuntate so far....you are doing the right thing looking into this further as you are his number one advocate!