My wife and I got both shots at the same time a month ago; no after effects at all.
As a bonus the pharmacy (Hy-Vee Supermarkets) had a deal that every flu shot would give the recipient a 20¢/gallon discount on the next fill-up at a Casey or Hy-Vee gas station. Neither shot cost us anything except about a five minute wait.
The flu shots saved us $3.72 on the 9.3 gallons I squeezed in today for the 323 miles that I have driven about town since the last fill-up a month ago.