HELP! EVERYTHING IS OFF

I just did a water change yesterday, it was NOT like this. I woke up and I notice my betted eye was just BLACK so I tested the water and just AHHAA?! idk what to do! She's in a smaller tank and I havent put together the 10g one I have in storage yet since since I don't have alot of equipment.

What do I do? Do I do a full water change? I used the conditioner from nutrafin aqua + and changed her filter. I did have to throw out the carbon bag and didn't get a new one yet.

Im very new to this, im slightly panicking, I just want to keep her healthy what the hell did I do wrong please help 😭

I just did a water change yesterday, it was NOT like this. I woke up and I notice my betted eye was just BLACK so I tested the water and just AHHAA?! idk what to do! She's in a smaller tank and I havent put together the 10g one I have in storage yet since since I don't have alot of equipment.

What do I do? Do I do a full water change? I used the conditioner from nutrafin aqua + and changed her filter. I did have to throw out the carbon bag and didn't get a new one yet.

Im very new to this, im slightly panicking, I just want to keep her healthy what the hell did I do wrong please help 😭