Am I having contractions? FTM HELP


I was 2cm and 50% effaced Tuesday at my dr appointment, Im 35 weeks today. I know I can be stuck at 2 for a long time but yesterday I went swimming and then bounced on a yoga ball last night. Today I went out on the boat and every time I moved or stood up I had bad pain in my stomach but mainly my lower stomach. When we came to load the boat and I was walking to the truck I could barely walk because it hurt so bad to move my legs/open my legs. Im a FTM so I’m clueless. Could I be having light contractions?