You must be continuing this medication under the guidance of the doctor as per my view. At this dose, side effects chances are least. As a part of routine check up you can done your investigations as RBS,
LIPID PROFILE, weight monitoring. Along with medication you can follow sleep hygiene, relaxation exercises also, gradually may be your sleep get better even on low dose. You should discuss with your doctor also, do not adjust dose on your own
Next Steps
follow what discussed above