Two legitimate SSN#'s assigned to one person?

I was born in the middle of a divorce. Initially, when I was born, I was assigned a SSN# with both my mother and fathers last name attached, un-hyphenated (ie;John Joseph Kennedy Smith). Soon after, the divorce was finalized, and my mother somehow had another SSN# and birth certificate assigned to me with out my fathers last name (ie; John Joseph Kennedy).

I went under that name (mothers maiden) all the way through school into college. Our family home burnt down and most of our records were lost. However, I found the copies of my original B.C. and SSN card with my fathers name attached. Not knowing the difference in numbers at the time I began using that as my I.D. I was just out of high school, working under the table, no loans, real bills, etc. and really never needed my SSN except for my Drivers License.

Now I'm just wondering if I've done anything wrong. I'd like to go back to just using my mothers maiden name but would that cause me problems? - Is this your question? Add additional information