Last week, strong first quarter results from Walmart (WMT)  helped boost sentiment for discount retailers and investors may be eyeing Dollar Tree (DLTR)  and Dollar General’s (DG)  stock ahead of their Q1 reports on Thursday, May 23, and Thursday, May 30 respectively.With that being said, let’s see if now is a good time to buy stock in either of these iconic discount retailers.Q1 Overview & Expectations Based on Zacks estimates, Dollar Tree’s Q1 sales are expected to rise 4% to $7.64 billion. However, Dolla ...