Stopped to get gas and she would not start up

[7d1truckguy]

I have a question, I put a new battery in my 1971 gmc less then a week ago, and went to get it inspected, and passed, I am driving home, and I stop to get gas, get ready to leave and the truck would not start. I had power to the radio, heater, and lights but it would not start when I turned it over, Pushed it out of everyone elses way checked connections, and checked under the dash, I seen 2 plastic connections that had come apart, so I reattatched them and It started right up, got it home and in the shop, shut the truck off and disconnected the plastic connection and tried to start the truck thinking it would not, Wrong it started right up, Could it be my starter doing this. HELP THANKS