I have had diabetes since 2002. I am scheduled for bariatric surgery on August 9th, not 100% decided.
I have never had a fast drop in BG in the 8 years since I became diabetic but I do get some very low morning fast readings on the pre-op very-low-carb diet I am on. If my BG reads 70 in the morning, I add some frozen berries to my breakfast protein -- the carbs in the berries bring me back up fast.
Of course talk to a doc, see the endocrinologist but I think you can help yourself avoid the way you feel with the very low BG. Be very careful. Test your BG a lot. I am surprised your doc did not give you some advice in the meantime, or refer you to a staff person with diabetes expertise. Most clinics these days have diabetes experts. My clinic has a nurse practitioner that is easy to get in to see and he helps me when I can't get an appointment with my doc -- appointments with my doc are hard to get.
Don't wait until August to make some changes.
With a glucometer and lots of testing while you wait to see the specialist, you should be able to adjust your carb intake. Maybe chillax about the weight gain. Redouble your commitment to eat healthfully to maintain your weight loss. I am learning that the more data I have, which means the more closely I pay attention to what my body is doing with lots of sugar testing -- before and after adding some carbs -- this close attention has many positive effects. I become much more conscious of what I am eating, which, in turn, influences me to make wiser choices. I also become much more aware of how I feel and feeling good feels good so it is natural incentive to avoid poor choices.
Take very good care of yourself.
It must be a little scary to have the low blood sugar drops.