No one can answer your question w/o evaluating the phrase that's registered as a trademark, the goods or services that are branded with that phrase, and your website. See the response to a very similar question here: http://bit.ly/68zCLr
FYI -- the dashes between the words in your domain name will be ignored when evaluating the lawfulness of your continued use of the domain.
The questions you ask at the end -- "Don't know if it means anything" -- probably don't. But to get the answers you are looking for, you have to sit down with the actual trademark and an actual trademark lawyer and see just what rights the other party has, what rights it could have, when it had them, etc. It is very possible that you can continue doing what you're doing, but the specifics make all the difference in the world.
As noted, virtually all trademark infringement questions are answered on Avvo with "it depends," because the specific details involved in your situation need to be disclosed and evaluated, and Avvo isn't the forum to do that.
Generally, however, domain names are not equivalent to trademarks, and don't necessarily confer rights superior to TM owners' rights. Questions of whether you've used the domain name as a mark, rather than just as internet address, how long you've used it,how long your competitor has used their mark and how long they've had a registered TM, whether your competitor has a U.S. TM or another state's TM, etc., all matter and need to be analyzed, and then the two names/marks and uses need to be compared.
See an IP lawyer to do this.
Disclaimer: Please note that this answer does not constitute legal advice, and should not be relied on, since each state has different laws, each situation is fact specific, and it is impossible to evaluate a legal problem without a comprehensive consultation and review of all the facts and documents at issue. This answer does not create an attorney-client relationship.