It keeps flashing on and off and won't go to any menu screen should I hit the reset and if so will I lose all my music

What make and model mp3 player?

Would not expect that a reset would lose your music but without truly knowing the problem the lost of data is a possibility. Could lose your music no matter what.....

The key is to identify what the flashing may mean or indicate; e.g., low battery, corrupted memory....

Do you have the User Guide/Manual? Look in the Troubleshooting Section.

Visit the player's manufacturer's website: Forums and FAQs. See if anyone else has reported a similar problem or related question.