Testicles don't come into sack

First am 32 years old and they have been down up till my yearly 20s then one day they went up inside and only came down one at a time now and then I can feel them and know there still there I am over weight due to a sports related injury and only really thought about it when trying to conceive with my wife and not getting anywhere I've a drs appointment in a few weeks (only spot they had) I am loosing weight but it's a slow journey and google is only making things worse and I don't know needed to put this down to get people opinions I guess or views I see it hurts my wife with every passing negative test she does I've told her the problem and we are going to face it together am a little worried as my father passed away in 2001 to testicular cancer