Hi, Holly! This is definitely a question for you OB/GYN. You mentioned this puts a strain on your weight loss. Your weight loss days are over for the next 8-9 months.
You can certainly get activity and eat right and gain an appropriate amount of weight.
I know many women that started a healthy lifestyle when pregnant and actually weighed a few pounds less after delivery. Just please don't focus on weight loss right now. Look over guidelines of what you should be eating while pregnant, stick to those, and get your doctor's advice on how much to exercise. They don't want you to gain an unnecessary amount, either so he/she will keep you on the right track.