These reddish circular patches on lower limbs
appear to be due to fungal infection
,which is quite common in people suffering from uncontrolled diabetes
Treament involves local application of anti fugal creams like CLOTRIMAXOLE,which is an OTC product and easily available.
Control your sugal levels meticulously.
You should be quite relived in a week's time and should keep applying the ointment for at least one week more after the complete resolution of skin patches.
In case there is no improvement,you should consult a dermatologist