there are ways to tell that you've crested into middle-age, leaving youth behind. if you should, say, wake on a saturday AM and think going to the japanese garden is good idea, that might be an indication. Further, if while there you should happen to, say, wander in to a presentation of ikebana and find it fascinating, inspiring and moving, that would be another. If after that lovely experience on a lovlier autumn afternoon, you found yourself looking at couches on hawthorne or, say, at the mall 205 home depot purchasing toilet seats, anchors, bamboo blinds, rubber gloves, fire extinguishers, wood stain and brushes willingly, that would be a resounding and thundering confirmation that you are now in your mid 30's and no longer can claim 'early 30's' even though you feel no real difference between yourself now and yourself then. What can you do but submit. And surrender.