[Type 1] Problems with low blood sugar

I've been a type 1 diabetic for about seven years now and this has never happened to me. I keep waking up in the middle of the night with low blood sugar levels (around 50 mg/dl). This has been happening for maybe 3-4 times a week for about a month now. I've been taking the same dosage of insulin (20ml of Lantus a night, 10ml per 1 gram of carbs), though I'm gonna start modifying that so I don't drop so low so often. I've been eating less because I'd like to lose weight and I've been going to the gym regularly to help with my health overall. I know going to the gym should help the blood sugar levels but should it be making my levels dip so low in the middle of the night? I have an appointment with my endo soon so I'll talk to her about it but what do y'all think? Anyone have similar experiences? Thoughts?