Hai mama! 28 weeks and baby moving low with tightening is actually pretty normal at this stage, baby's still repositioning, and Braxton Hicks (those practice contractions) are super common. But since you're a first-time mum, it's best to check in with your doctor or midwife just to be safe and get peace of mind, okay? They can confirm everything's progressing well. A few of my mum friends had the same worry, and after seeing their gynae they felt so much better! Take care, and don't hesitate to reach out to your clinic if the tightening gets too frequent or painful.