I don't know everything about regexps, but a dot should be escaped, or it will be treated as "any character". A dot matches any charachter if it is not escaped properly.
Same goes for the comma and dash, backslash and ', in other words, all characters that have a function within a regexp. They should all be escaped properly. [A-Z] means A to Z, while [A\-Z] means A, - and Z.