Americans started to receive the Pfizer/BioNTech coronavirus vaccine Monday morning, marking a major milestone in the fightback against the pandemic that has hit the United States harder than any other nation. One of them was Sandra Lindsay, a critical-care worker from Queens, who became the first New Yorker to get the shot outside of drug makers’ trials. “I hope this marks the beginning of the end of a very painful time in our country. I want to instill public confidence that the vaccine is safe,” Lindsay told New York Gov. Andrew Cuomo in a livestream of her historic vaccination. President Trump tweeted shortly after Lindsay’s shot: “First Vaccine Administered. Congratulations USA! Congratulations WORLD!”