Nikon Pro's - ISO Auto issues

I'm new to DSLR photography and have been playing with and enjoying my D5100 for about 3 months. Today while playing with Macro photography (using macro mode on the dial) I heard several short and long beeps (I think 3 of each but can't remember).

Now, even though my Macro dial ISO setting says "Auto ISO" in view finder and "Auto ISO" in "info" screen, all shots come out at ISO 200 regardless if I'm outside on a sunny day, or in my house at 8pm with very little light. This only happens when dial is set to "Macro". All other dial settings seem to work correctly in regards to showing ISO Auto in the info panel and actually taking the picture using the correct (auto) ISO.

My troubleshooting to this point I have done to try & solve problem
1.Turned off camera and turned back on (did not solve problem) I thought maybe somehow I locked the exposure to 200 and that turning off/on would reset it but nope.
2. Turned off camera, removed battery & replaced battery & turned back on (did not solve problem)
3. Reset Shooting Menu under "Menu" (did not solve problem)
4. Factory Reset by pressing Menu+Info button at same time for 2-3 seconds (did not solve problem)
5. Tried a different lens (did not solve problem)
6.Info Screen, changed ISO Auto to ISO 800 took picture and picture captured at ISO 800. Went back to Info screen, changed ISO back to "ISO Auto" and view finder shows "ISO Auto 1600" until I try to focus, as soon as i press 1/2 way on shutter button to focus "ISO Auto" disappears and "ISO 200" reappears regardless of available lighting (outside in the dark, outside in the sun)

This only happens in "Macro" on the program dial. All other settings on dial that use ISO Auto (Landscape, Portrait, etc) use ISO correctly and take picture at correct ISO.

I have tried google this and can't find any answers. I'm assuming the beeps I heard have something to do with this new issue since I was in the "Macro" setting on dial when I heard them and this is the only setting on dial that no longer seems to work correctly. Somehow some way in my newbie excitement to play with macro pictures, i told my camera to override ISO Auto and always use ISO 200 when dial is set to Macro - but how?

Help! Having lots of fun with my new camera, hoping its a newbie mistake and easily fixed, just don't have the experience to know what or how beyond the common sense troubleshooting I tried above.

Any help greatly appreciated

Using any of the scene modes in a dSLR is just like using a point-and-shoot camera. You can't touch all or most of the settings. Most probably, the beeps are there to warn you to stop fiddling with the controls. The best way to do macro is to use a macro lens.

You have limited your ISO to the 200 max. How you change that in a Nikon camera is not something I can tell you, I'm a canon kind of girl. I'm sorry. You'll need your manual and have to find.

As you are new to your DSLR I HIGHLY HIGHLY recommend the Magic Lantern Guide for your camera. It tells you everything the manual fails to tell you.

Macro mode on a DSLR is just a quick way of setting up "okay" settings for a particular task, it doesn't do anything that you couldn't do in manual mode. In this case one of those settings it's making on your behalf is setting the ISO to 200 rather than use the Auto ISO you have the camera set up for as default. As a standard rule I'd only use the "modes" on such a camera if I was in a rush, try instead to learn how to do everything manually if you can - in the end "manual" will give you far greater flexibility.