Looking back, my weight stopped increasing around the 37th-38th week. So don't worry, it won't keep rising forever, your body naturally prepares for delivery.
Usually, the weight gain slows down significantly in the last 2-3 weeks of the ninth month. By then, your stomach is so crowded that you can barely eat full meals anyway!
I noticed my weight stabilized in the very last month, which was a relief. Focus on keeping your BP tests normal rather than worrying about the weight scale now.
I totally understand the anxiety of seeing the scale go up constantly. It usually plateaus in the last month, so take a deep breath and cherish these last few weeks.