You should use this test result as a wake-up call to eat healthy, exercise often, stop smoking if you do,
reduce drinking, take vitamins and supplements,
reduce stress and increase rest. He should do the same.
The bottom line is you have no idea if he gave it to you or if you gave it to him. And that is the way to aproach this if you decide to tell him. At least you can be tested. Us men have to remain clueless, get a wart or depend on our lovers to tell us the bad news.