Minor Error in Submitted Elsevier Journal Paper
First of all, that it's Elsevier doesn't seem to have anything to do with it.  (Unless you didn't want to submit there at all, but evidently you do, which is fine by me...)

Based on your description of the errors, I agree that they are minor.  In my experience, many if not most papers contain minor errors of this form, and a lot of referees include it as part of their job to point out the minor errors that they find (though of course you cannot count on this).  If the minor errors are sufficiently numerous that creates a bad impression, as would minor errors that are not viewed as minor (obviously).  


  I would be very disappointed if they were to reject the paper on these grounds. 


In the great game of journal submissions, anything is possible.  If it happened it would be a raw deal.  Raw deals occur relatively frequently in this game, and I know of no way to systematically protect against them.  In this case, being a bit more careful is obvious advice, but don't take it too seriously: one could spend twice as much time proofreading and still have minor errors.


  I hope they wouldn't assume I don't know the content of my area because of this mismatch.


To me that seems even more unlikely and also a bit off-center.  The task of a referee is not to judge you but rather your paper.  Full mastery of the content of your subject area is neither necessary nor sufficient to get your paper accepted, I would say.

In terms of what to do, you have two options: either wait patiently for the outcome, or contact the editor saying you found some typos in your paper, have prepared a new version, and are willing to pass that along to the referees if they think that is a good idea.  My advice: if it's only been a couple of weeks since submission, probably the referee has not sat down to read the paper carefully yet.  (At least that's the way it is in pure mathematics.  If it's otherwise in your field: congratulations.)  Sending along a fresh version will probably be well received.  (If it can be received.  The automated journal submission systems complicate this a bit.)  If it's been much longer than that, the referee may have already been through this part of your paper, and sending a revised version is asking them to look at two versions of your paper at once, which is a bit annoying.

Anyway, try not to worry about it.  Others have done this and worse than this many times over.