Accies lost goals late in each half to let slip a lead in a 2-1 defeat which left them seven points adrift at the foot of the Clydesdale Bank Premier League.
The match could easily have turned Hamilton's way late on but referee Willie Collum only awarded them a free-kick when Dougie Imrie was fouled by Timothy van der Meulen, seemingly inside the box.
United substitute Jon Daly, who underwent hernia surgery three weeks ago, then slotted home almost two minutes into injury-time following a clever reverse pass by David Goodwillie, who had levelled towards the end of a first half Hamilton dominated when the ball broke kindly for him after a Barry Douglas corner.
Hamilton had been well worthy of Flavio Paixao's 26th-minute opener and Reid, who named wingers Imrie and Jim McAlister in a makeshift back-four, feels his players are due a turnaround in fortunes.
He said: "It's not as if we're not in matches, I don't think anyone could say that. We applied ourselves in the right manner, our shape was great and we matched United pound for pound. I realise the size of club we are and it's important we keep a spirit about us and we keep trying to do the right things. Performance-wise in the last five to six weeks I have been absolutely over the moon. But for some reason the guys have not had a break when they need it."