After reading a LinkedIn article by Shane Snow I was knocked back to process how often I interchange the words thinking and feeling. As a feeler, I know from my marriage (to a thinker) that I have to often preface what I communicate with "where I am" and what I need from him as a deliberative processor.
The internal response to starting sentences with "I think" or "I feel" is important, but most important when we do it wrong. When we say we feel something but it is really an opinion not a thought, of vice versa is one reason we have confusion internally and in our interactions with others.
Recall your Myers Briggs or 16 personalities outcomes, as those are built upon Jungian Type Theories. Be aware and do better!
I challenge you to intentionally inventory your use of these two simple words for a bit to see how you do!