I think it will be fine if you both like it. My ds2 goes by his 2nd name. He knows his full name, as well, but always goes by the middle name. People shorten for nicknames all the time, too. I was always more afraid of someone shortening my ods' name to something I didn't like, like Joey.
Wife to Joe. Proud, tired mommy to Captain Destructive (6/09), Sir Screams-a-lot (8/10), and another little miracle due 3/13.
Trusting God brings life. Believing brings rest.