When is it right to say "I'm sorry!"? When we make a mistake, disobey God, or hurt others we need to apologize for sure. God is pleased with a truly repentant heart. However, how often do we say "I'm sorry" over and over again? Why wasn't the first time enough? Do we think God will not forgive us the first time? Do we have a problem forgiving ourselves? We need to remember 1 John 1:9, "If we confess our sins, He is faithful and just to forgive our sins and cleanse us from all unrighteousness." God forgives us the first time we ask forgiveness. When we do not forgive ourselves we are putting ourselves above God. God is God. If He says someone is forgiven, they are forgiven!
Another time we say "I'm sorry" when we shouldn't is when we apologize for doing what is right. This has been brought to my attention recently. If I have convictions to do what is right, I shouldn't tell someone "I'm sorry." We do not have to apologize for God. If He works through us, we should not apologize for it. We need to just obey His promptings and leave the rest to Him.
I've seen people apologize for acting in a way that their natural personality functions. That is not something to be sorry about. God made us all different to fill different needs. Of course we all have strengths and weaknesses. God will show us those weak areas of our personalities that we need to surrender to Him to bring maturity. When we fall into the weaknesses, then an apology may be in order, but we need to trust God that He will use those times to fine tune our strengths. We should never apologize for using strengths that others do not have. They need us! We need them! When we realize that, we will not be offended or feel that we have to always say "I'm sorry."