Yeah… Although 14 hours is a little on the higher side, I wouldn’t worry about it too much. It doesn’t affect your important stats. in any way; prospective buyers will still be able to contact you.
Another thing I would like to point out is that the 14 hours shown is your response time (and not your response rate; they’re different ). The response rate is a more crucial stat. than the response time. In order to maintain your response rate at 100%, you should reply to the first message (in your inbox) from a new user within 24 hours.
Now coming back to your response time: you can improve (reduce) your response time by replying to future messages as soon as you possibly can. This is where the Fiverr app can come in handy. The app can be configured to send push notifications/alerts on your phone as soon as you receive a new message or a new order on Fiverr. This way, you will (probably/hopefully) be able to respond to messages faster, and this will reduce your response time. The lowest response time you can achieve is 1 hour.