Do I get revisions when I use DesignCrowd?

Yes.  Revision requests work differently for Design Contests and One-Designer Projects.  Here is an explanation of the difference:

Design Contest Revisions

There is no cap to the number of revisions a business can request for design contest projects and designers will almost always complete revisions although they have a right (if their design has not been selected) to not complete revisions. 

There are two types of revisions:

Free Revisions: Businesses may send messages of feedback and requests for revisions to designers.  Designers are almost always willing to make minor changes (to color, layout, font and the words used) to the designs they are submitting, as long as the revisions required are within the scope of the brief.  If designers do not want to submit revisions, you may need to guarantee them that you will award them the job or need to pay them for the revision work.

Paid Revisions: Designers of projects where you do not want to guarantee revisions may request payment for the revision.  It is up to the business whether or not they wish to pay for these revisions.

One-designer Revisions

When you run a one-designer job where you work exclusively with a single designer you will be given an automatic 3 revision rounds. Often, a designer will be willing to provide more revisions than this as part of their customer service to you.