What happens if I accidentally gave myself humulin (insulin)?

Which insulin. Humulin is the brand of insulin. Is it regular, nph, humalog, (insulin lispro) mixed insulin, etc? Low blood sugar is high risk, but the timing depends on which Insulin you took, how much you took. Was it your intention to take one form of Insulin and you took another by mistake? Please contact your endocrinologist also.