Welcome to HCM
You are Type II Diabetes and taking Basal Insulin Lantus, it is not enough to control sugar level as there is insulin resistance
and you have missed metformin
tab hence blood sugar level is high.
High blood sugar level does change index of lens of our eyes hence visual disturbance.
You can use Regular insulin
additional doses before lunch and dinner in consultation with treating Physician.
Once blood sugar is controlled oral tab can be started again.
You have to take care of your medicine stock.
I do not understand why you can not procure new stock?
I would suggest to consult doctor
first as sugar level is high.
Good Luck to you