I've Been Novolog Insulin 2 Weeks . I'm Supposed To

I've been novolog insulin 2 weeks . I'm supposed to take my blood sugar test 4 times a day.and take a small amount of insulin according to what my blood sugar reads .Sometime I only need 2 units and never over 8. My directions says if it's over 400 to take 12 units and wait 1 hour and take it again .The next time it was over 400 again . Is it safe to take that much insulin so close together?