Nervous but excited

I am a First Time Mom. Today I had my 38 week appointment. Baby's heart rate was fantastic. My mild weight gain was good too. I had a few questions that my doctor answered very well. The biggest question was that for the last few days, I have been experiencing some moderate to severe back pain that comes and goes in waves. It hasn't been consistent enough to track but it has been annoying enough to throw off my daily activities. My doctor said that unless its accompanied by tightening of the uterus and abdomen, its not labor. However, when my mom had my older sister, all she had was back pain. No other signs of labor. I'm currently 1/2 to 1cm dilated. Nothing too big. I'm trying to track the waves of back pain to see if they are becoming more consistent. I'm just not sure if this is the early stages of labor or not.

Anyone else experience just back pain before labor set in?