Should I be getting paid overtime for working a double shift?

In your state, when you have a "split shift," or two shifts separated by more than an hour, you do NOT get the full amount of time, from the start of the first shit to the end of the second, as paid work time. Rather, you are entitled to one extra hour of pay at minimum wage. And furthermore, any pay you received for your work hours at more than minimum goes against and can be used reduce that extra hour of minimum wage pay. You are working 7 hours of actual work; that means that if you are receiving as your base pay more than 1/7th over the minimum wage, then since 7 hours x 1/7th over minimum equal at least one hour at minimum, you will in fact not get the "split shift" extra hour of minimum wage pay. In short, unless you are minimum wage, the "split shift" doesn't really help you, and  even if you are, you only get one extra hour of minimum wage pay. The law in your state for split shifts doesn't really compensate you for the disruption in your day. 
You may wish to do what I do: when I appear in court, if a case extends across the 2 hour long judicial lunch break, I have two hours to kill which I cannot bill the client for (it's lunch). I therefore always bring with me materials so I can use the time productively: reading, bills to pay, emails to send or respond to, my taxes to work on at the appropriate time of year, etc. I prepare myself for having time to kill and turn it to my advantage.