That is completely fine. That happens frequently to me now.... my memory has become so bad. sometimes I am totally lost of words. most of the times, my husband will finish the sentence for me, and that is alright. he takes the cue when to subtly complete my sentence.... another example of my memory lapses - i put a cup in the microwave just with the tea bag but without water! My family, friends, and previous co-workers used to consider me as a walking filing cabinet because I memorize every single details, but now, that is gone....sometimes I am frustrated but with all the more serious problems I have with the pain, memory lapse is a lesser evil.