Oreint midfielder Dean Cox scored the only goal of the game in first-half stoppage time as Coventry's last home game ended in disappointment.
Coventry dominated possession throughout, but could not find a way through.
Pressley said: "Again the final finish or the final pass just let us down, that's the disappointment because there were so many positives to take from the game.
"After dominating for such long periods of the first half it was a bit of a hammer blow to concede just before half-time.
"We responded in the right manner in the second half.
"If we are to make an impact next season we need to take care of our home games because generally those at the top end of the table are very strong at home.
"It's been a difficult season in terms of a lot of uncertainty around the football club.
"It would be wonderful if we could have all those aspects cleared up before the start of next season and we can have a real unity throughout the club because we all want one thing and that is a successful team on the park."