Ahhh Braxton Hicks ke tu! I had the same thing around that time, macam perut tight je and then hilang, so scary kan first time! A few of my mum friends said theirs started around 32-33 weeks, mostly when tired or dehydrated, so minum banyak air and rest lebih-lebih. But since you're already at 33+ weeks and experiencing this, definitely check with your doctor or midwife just to be safe, they can confirm it's just practice contractions and not anything else, and it'll give you peace of mind. Hang in there, you're almost there!