Ingress: Creating fields within fields.

So...not sure if this is a glitch or not, but I created a control field within a field. Sorry if this has already been discussed and I'm just late to the conversation.

Unfortunately I didn't get a screenshot of the portal you can see below as a farm, without any links. And I even tried seeing if I could link to any of the portals that anchored the field it was within, but I couldn't.

However, curiously, when I went to one of those anchors, I found I could link in. Then I did it with another one, and not only did it link it, but it confirmed that a control field had been created...within the one that was already there. So I had one more anchor in the larger field to go to, and I do have photos of the change.

Before:

Here's the confirmation message that fields were created.

And here's the after: 

I was afraid it was just my imagination, but the double field actually shows up as a stronger green. In case you can't see the difference from the screen shot, here's one from the Intel map online:

Thoughts? What's going on? Does that mean that the mind units are counted twice because they are twice as influenced by the control field? Or is this probably just a glitch?

Like I said, while I couldn't link from the interior portal to the anchors of the larger field, so from inside to the perimeter, I could link from the anchors to the portal within the field.

Anybody else come across this already?

Curious mind wants to know,

JR