Symes took his tally for the season to six when he applied a superb finish to a well-worked corner routine as Cherries registered a 1-0 win at Bescot Stadium.
The 27-year-old was on hand to convert from just inside the 18-yard box after Liam Feeney had foxed the Saddlers defence by stepping over Marc Pugh's delivery.
But while his 52nd-minute strike may have kept Cherries firmly in the hunt for promotion, Symes later revealed he had been guilty of a set-piece faux pas.
Speaking to the Daily Echo, Symes said: We've got two similar corner routines and we work on them both in training every week. There is one when Adam Smith comes forward and shoots and one when I curve my run from the back post and shoot.
The way we set up for both is similar and, to be honest, I got a bit mixed up and thought we were doing mine when actually we were supposed to be doing his!
As I was making my run, I saw Smithy coming in and realised I wasn't supposed to be having a shot. Luckily for me, it went in and nobody was complaining.
You could say there was an element of good fortune about it but everyone was delighted because it was the only goal of the game and won us the points.
After I had scored, I ran over to the bench to apologise and celebrate at the same time. They knew I shouldn't have been there but they were all made up as well though.
Symes was roundly booed by the Saddlers faithful after he had tried to claim an early opener despite deliberately handling Liam Feeney's cross past goalkeeper Jimmy Walker.
But the skilful striker, who has experienced mixed fortunes during his debut season with Cherries, had the last laugh when he converted the winner seven minutes after the break.
Symes added: Everyone knows I had a bad injury and then found it hard to get back in when I was fit. That was down to Fletch doing so well and the lads winning. I couldn't really complain to Eddie (Howe) at the time and him and Jason (Tindall) were brilliant with me.
Thankfully, Bradders has taken over and has given me a chance. Hopefully, I can repay him with as many goals as possible. It is good for me having a manager and assistant who are both strikers.
They have got a lot of experience so can point me in the right direction.