Should I change my filling?

so I went to the dentist that place doesn't seem all that busy anyway and she offered to change all of my filling just cuz they're old so on next appt I told the dentist that I'm not changing them that they don't bother me and I don't want and she goes like yeah well than you shouldent but you should get at least one changed just cuz it's leaking... So I'm just wondering should I change it or not or is she just trying to get more out of the insurance... To be honest my teeth don't bother me what's so ever and about 6 months ago when I was at a diff dental they never mentioned anything about my fillings... So I'm a bit confused and not sure.... Should I let her dig one out and put a new filling on? I just don't want my tooth bothering afterwards. ( I went to dentist to get my teeth cleaned)