Brighton were 2-1 down with 20 minutes to play after goals Richarlison and Doninic Calvert-Lewin had cancelled out Pascal Gross' excellent first half freekick.
However, VAR deemed Michael Keane's stamp on Aaron Connolly's foot enough to warrant a penalty - one that Neal Maupay calmly converted.
An own goal from Everton captain Lucas Digne from Leanro Trossard's dangerous cross, sealed the memorable win for Albion.
"My heart needs a bit of a rest after that," said Potter. "To turn it around like we did is an amazing feeling. "It was an important moment to get the equaliser and there was a feeling in stadium for us to push on and get the win.
"I haven't seen replays of the penalty. We have had a few that have not gone our way recently. We have earned a bit of luck. We didn't play our best and it was a tough match. We had to dig deep."
The win moves Albion up to 12th in the Premier League table on 12 points from 10 matches. Everton are just two above the drop zone with 10 points from 10. Needless to say, Everton boss Marco Silva was fuming with the VAR decision.
"If VAR saw something in our box, why didn't it see 15 minutes earlier the penalty for Richarlison," he complained. Because of that my players are in the dressing room and don't understand.
"If they see one for one side then they have to see for the other side too. It was a clear penalty [to us]. VAR has to be the same for both sides."
"We have to be more mature to control the last 10 minutes. It's a tough moment for us. We have to stick together.
"We conceded the first goal but after that we reacted strongly and as a team. We created some dangerous moments."