Any chance those emails are your email address without a dot that is supposed to be in the address? Eg. I'm getting messages all the time sent to [email protected] when my address is [email protected]. Google treats these as the same, but apparently someone else believes they have set up firstlast as their address. Google insists they won't let a second address be registered with the only difference being punctuation, but my online searches suggest a lot of people have this issue. Google (or whoever is responding to the messages) says the other person must be forgetting what their actual email address is.

It's amazing the variety of sites that are requesting I click to complete a registration. Latest is some college sports recruitment company. It looks like the kid wants to play football. I'm 99% sure the ones I'm getting are legitimate emails. They got past the gmail filters and that almost never happens for junk mail.