I breast feed my two month old full time and express from each breast in the morning for use if I'm out and about in the daytime. Should I be expressing in the evening as well to get my milk supply up for 3 month growth spurt ?
Your baby will do a perfectly good job of demanding more when she / he goes through a growth spurt - no need to express. That's the amazing thing about BF (when it works - ie in the majority of cases) - it just adjusts to suit your exact baby. Trust your body!