Donald Trump’s hush money trial proceedings began with jury selection on Monday, April 15, but the embattled ex-prez wasn’t pleased when he learned that the case would likely still be underway on Friday, May 17, when his youngest son, Barron, 18, is set to graduate high school. The trial is happening because the 77-year-old was charged with 34 counts of falsifying business documents last year. However, the frustrated former POTUS took to Truth Social to personally blame Judge Juan Merchan for the situation. “Who will explain for me, to my wonderful son, Barron, who is a GREAT Student at a fant…