Wow that sounds like a really bad reaction. Sorry to hear that, but hopefully you are ok.
Have you never taken oil of oregano before?
It is a very powerful antifungal, but also an antimicrobial which means it will kill bacteria, good and bad.
For one you’re supposed to take probiotics first thing in the morning, on their own with at least a half glass of water, with nothing else so it doesn’t interfere en route to the gut.
For two, you should only take antifungals at least an hour away from the probiotics since many are antibacterial, such as the lemon water you had. Make sure you split them apart from now on.
My guess is not only did you kill many of the good bacteria, you may have a sensitivity to oil of oregano such as it says on the bottle. Do you have any reactions to similar plant species – lavender, basil, thyme, mint…?
You could try adding the drops slowly, starting with 3 a day.
1 drop in a glass of water X 3 about 30 minutes before a meal each day.
Then as you overcome any die-off, up this until you’re able to have 3 drop 3 times a day.
Do not go overboard with oregano oil, since you are taking probiotics and this will destroy them too.