If the system can’t send out a password e-mail, or any e-mail for that matter, it will flag it in the error log for me as a problem.
This was quite apparent in November when I made a server change and forgot to update a setting and ended up with 28 pages of errors for watched topics. :spank:
The error log has been empty since then so that means the e-mails are going out, and as suggested, most likely your e-mail address in your profile is old or possibly spelt wrong, resulting in no e-mail.