I just messed up my gmail organization real bad. Does anyone have any ideas how to fix this?

I have a lot of filters in Gmail, I use them to automatically apply labels (folders) to each of my emails. For instance I recently created a filter that says:

Code:
Matches: pemco
Do this: Apply label "2017-07-12 Rear-ended accident on 520"


That's just one example. I have many dozens of such filters. I have many filters which, based on certain keywords, keep all of my purchase receipts and shipping confirmations in one folder. I have filters which sort house maintenance information into one place. I have filters which sort tech support response messages. I have filters for band gig information, filters for convention info... I even have a filter for Empeg information. These filters and labels/folders have all worked well for years.

Here is an example of some other filters I have that already exist:

Code:
Matches: patient-message.com
Do this: Apply label "Medical"
Matches: swedish.org
Do this: Apply label "Medical"
Matches: [email protected]
Do this: Apply label "Medical"


So as you can see, I have several filters that add the "Medical" tag to certain emails I regularly get from medical providers. But here's what's important with this:
- I do not ONLY sort my mail with filters. For instance, I frequently apply labels to certain one-off messages by hand.
- For example I might get an email from someone and I might apply the label "Medical" to that email by hand, over the years.

So now I have a folder in Gmail called "Medical" which is fine, it has in it two different classes of message from over the years:
- Messages which I have filtered with filters into the "Medical" folder.
- Messages which I have hand-labeled with "Medical" myself in the "Medical" folder.

Today I got an email from a different medical provider system. It came from a different address than the others (it came from [email protected]). I added a new filter which I THOUGHT would have been this filter:

Code:
Matches: [email protected]
Do this: Apply label "Medical"


This should have worked fine. However, I must have made a mistake. Somehow it became a NEGATIVE filter. I don't know how that happened. The filter turned out to be this instead:

Code:
Matches: -{[email protected]}
Do this: Apply label "Medical"


Now here's the problem:
- Every email for all of my history forever is now in my "Medical" folder. All except the ones I was trying to get in there in the first place!

What I want to do:
- Remove the filter (easy, I know how to do that, just go into settings and delete the filter, I already did that).
- Undo the damage that the filter caused (this did not happen automatically when I removed the filter), and do so without losing my previous careful assignments of things which went into the "Medical" folder by hand.

I tried googling for this, and the only answers involved returning the filters themselves to their original state, but not how to perfectly undo the thing that the filter *did*.

I'm stumped as to how to fix this. Anyone have any ideas?

_________________________
Tony Fabris