Dulwich Hamlet manager Gavin Rose praised his side after they inflicted a first defeat on the leaders of the Ryman League Division One South.
But the good times soon evaporated after a mid-week 1-0 defeat at Corinthian Casuals - gifting them their first home win of the season.
Against Folkestone, two goals from Erhun Oztumer – a 30-yard curler and a penalty – consigned the league's to side to a 2-0 defeat and lifted the Hamlet to third place.
However, after the Casuals result, Dulwich slipped to seventh.
Rose said: “Folkestone are a strong team who have always been there or thereabouts, so this was a really hard win for the boys.
“We should have taken all the points from the Sittingbourne game. We should have taken our chances in the first-half and we suffered for that, and the Arlesey cup game was always going to be tough.
“We’ve been losing by the odd goal here and there and so we’re not pressing the panic button. In fact when you look at league results we’re doing OK.
“The league is yet to settle down because of all the cup games, but when it does we’ll get more of an idea where we are. There are quite a few teams in a pack around the middle and the top of the league and we’re in there.
“Give it a few more weeks and I think you’ll find out who the leaders will be and who will be in the chasing pack.”
Rose is struggling with an ever increasing injury list including long-term absentees Ethan Pinnock and Frankie Sawyer, while Ahmed Dean is suffering from recurrent injuries.
Meanhwile, Vernon Francis has signed forms with Tooting & Mitcham.
This weekend they travel to mid-table Maidstone.