I have seen the following signs and need to know if they may be dyslexia trouble spelling words, trouble retaining spelling of words, changing of letters B and D, numbers 5 and 3, trouble reading big words.

letters turned around or transposed, inability to read or write effectively, inability to read aloud

Symptoms

Possible family history of learning disorder
Difficulty learning to recognize written words
Difficulty rhyming
Difficulty determining the meaning (idea content) of a simple sentence
May occur in combination with writing or arithmetic learning problems
Signs and tests

The first step is to perform a complete medical, developmental, social, and school performance history. Physical and neurologic examinations are also necessary, followed by psychoeducational testing and psychological assessment. other causes of learning disabilities will need to be ruled out before the diagnosis of DRD can be confirmed.

It is hard to tell as dyslexia is quite a complicated thing. It might be dyslexia but to be sure, you need to ask e.g. a special-needs-teacher for his / her advice. Usually, you will get a test to be sure whether you have dyslexia or not.