Previously (until Feb 2017), we were not sending out confirmation emails when we receive a revision. Since March 2017 you now receive an email when you submit a revised manuscript.
You should be able to see the manuscript on your author homepage, and the status should have changed from "awaiting revision" to "under review".
Note that you must upload your revised manuscript, and on the same day send a notification email to the editor, detailing your responses to editorial and reviewer comments. Otherwise the paper may have been uploaded but the paper is not sent out for re-review (we need author responses first).
Related: