well that depends on many things not just QQ and lower flop.
-who am i playing,r eads ,reads reads
-how deep he is
-what is he doing lately on the table
-stakes

for example if i think someone is raising his tp on flop then i call him and see turn... if someone is set camping then i can fold right to his minraise...

3betting flop is cheaper hm?
to me 3beting wihto verpair is bad for simple reason ur jsut putting much of ur stack with 1 pari after he alread shown some agression. if u 3bet his minraise thats putting like 40BB right there on the flop.. with ur another minraise on the flop its still around 30... and if u 3bet preflop with highpairs then u cant even think about 3betting flop.