too early

See: premature
References in classic literature ?
Verily, too early died that Hebrew whom the preachers of slow death honour: and to many hath it proved a calamity that he died too early.
Their horses, although of the Nez Perce breed, are inferior to the parent stock from being ridden at too early an age, being often bought when but two years old and immediately put to hard work.
When I arrived, a little late, because in my fear of being too early I had walked three times round the cathedral, I found the party already complete.
Levin and others have said that early admission forces students to choose a school too early in the selection process, causing unneeded anxiety.