The Peoria Battery, Battery A, 2nd Illinois Light Artillery, was placed in the corner of a field facing to the northeast. A cannoneer later said that the battery's position was a mistake, as the rightmost gun was only 2 rods from the treeline. Davis's plan fell apart completely, as his Second Brigade was forced to retreat after running out of ammunition. The 37th Illinois retreated towards the guns and masked them, but the 4 Confederate regiments were pretty well mixed up after a 45-minute fight in the woods and were slow to capitalize on their success. They couldn't see because of the smoke, leaves were catching on fire adding to the confusion, they couldn't find their officers, and they really didn't know where the Federals had retreated to. They didn't receive any support from the rest of the division because both the division commander (BG Ben McCulloch) & his 2nd in command (BG James McIntosh) had been killed earlier & no one stepped forward to take command. They were able to capture 2 of the Peoria Battery's guns, but were forced to abandon them after only about 15 minutes. Davis's Second Brigade regrouped and attacked the Confederates as they fell back into the woods, forcing them into Davis's First Brigade. This caused a complete rout. Some (including the brigade commander) fled to the southeast and were captured. The rest retreated north back to the main Confederate position.
Bill Shea & Earl Hess wrote a great book on Pea Ridge (Pea Ridge: Civil War Campaign in the West). There are 2 good first-person narratives of the battle from the Confederate point of view, Will Tunnard's "A Southern Record" & William Watson's "Life in the Confederate Army" (both about the 3rd Louisiana).