Trump's low approval rating is not good, but its not a record low by any means.

President Donald Trump's job approval rating fell to 36% for the three-day period of March 24-26, following Republican House leaders' failed effort to pass a new healthcare bill that would have replaced the Affordable Care Act.
Trump's current 36% is two percentage points below Barack Obama's low point of 38%, recorded in 2011 and 2014. 

Trump has also edged below Bill Clinton's all-time low of 37%, recorded in the summer of 1993, his first year in office, as well as Gerald Ford's 37% low point in January and March 1975. John F. Kennedy's lowest approval rating was 56%; Dwight Eisenhower's was 48%.
Presidents George W. Bush (lowest approval rating: 25%), George H.W. Bush (29%), Ronald Reagan (35%), Jimmy Carter (28%), Richard Nixon (24%), Lyndon Johnson (35%) and Harry Truman (22%) all had job approval ratings lower than 36% at least once during their administrations.

Gallup,  here.