Eh, ini kena check dengan doctor ni, betul betul! Hyperthyroidism during pregnancy is something yang kena handle dengan proper sebab boleh affect baby, so jangan delay the blood tests okay, minta doctor refer you to specialist if needed, especially since you're already 31 weeks. A few of my mum friends yang ada thyroid issues during pregnancy, they kena monitor closely dengan thyroid specialist + OB-GYN together, so make sure you push for the full thyroid panel kalau belum buat. Breathlessness + fast heart rate during pregnancy boleh jadi banyak benda, tapi with the suspect, you really need confirmation dari blood work, bukan just symptoms. Jangan worry too much yet, kita tunggu the test results dulu, but please get it done asap. Doctor knows best, and they'll guide you on next steps once confirmed. Hang in there!