Time for another valve replacement?

I am a 41 year old male who has had two AVR's. Good health otherwise. 5'10 and 165lbs. My first AVR was a porcine valve done at 29. My current one was done 2 1/2 years ago at age 39, and it is mechanical.

For the past two months I have had heart palpitations. But they have recently subsided. Now  I experience chest pain in the center of my chest with exertion, like cardio or carrying heavy objects. It feels to me that it is a leaky valve again, or worse.

I'm fairly certain the valve is ok, because my wife can still hear the clicking. But I think it's the sutures breaking, from what I've read. I really don't like the fact that I might be facing my third AVR so soon. As a matter of fact I'm feeling somewhat fatalistic. This has stopped me from seeing the cardiologist about it, because I'm pretty sure he's going to give me the bad news of needing another AVR.

I was wondering, could it be something else? Has anyone else experienced something like this? If so, could it be something unrelated to the valve?