Albion had led after being gifted a goal by Nottingham Forest goalkeeper Keylor Navas.
Facundo Buonanotte was on hand on his Premier League debut to put the Albion in front.
Forest had an early penalty after Pervis Estupinan brought down Neco Williams.
Jason Steele saved the spot kick from Forest top scorer Brennan Johnson.
Julio Enciso then had a glorious chance but Navas saved from point-blank range.
Johnson had a another chance but his shot was wide.
It was Solly March who provided the cross that Navas palmed straight to Buonanotte to put Albion ahead.
Albion looked comfortable right until the end of the half when Renan Lodi saw his hopeful cross clatter into Pascal Gross and into the net for 1-1 just before the whistle for the break.
