What do period like cramps mean in third trimester?

Rachel • Di/di twin boys and one on the way👦🏻👦🏼👶🏼

Carrying twins and in constant fear of preterm labor🙈 33 weeks and I get mild to moderate period like cramps multiple times a day, especially if I’m active. Doctor said he’ll check me for dilation next appointment at 34 weeks but I’m curious if this is the started of dilation or effacement