Speeding Ticket Question :(?

I have been trying to do good driving and not getting any tickets, but I got one the other day, says on the ticket speed of 70 in a 55. Also says G.S. 20-141(B)(G) but I do not understand what that means? It was my first day in the rental car(not used to it at all) with a truck right behind me and a car beside of me going down a hill on I 40, I was unaware of the speed and he said he clocked me at 74 but was writing the ticket for 70. When i was 18 i got wreckless driving for a stupid burnout and a speeding ticket 10 over an some stupid one point unsafe movement between the ages of 16 and 18. I am 21 now. I just cant believe this. I have been doing good, not trying to get a ticket, now i look like a bad person with the past but i was young and STUPID. Now what should i do? I think i will get a lawyer, even tho the ticket does not say i have to attend court, I could just pay the fine i believe. Any ideas? state is North Carolina