The white in LO mouth could be milk stain. Milk stain will wipe off, thrush won't.
What about your clothes? Are you wearing bras multiple times? They should be washed after every time, you can add some vinegar to help kill it. You can also put vinegar water straight on your nipples and let them air dry.
Pacifiers, toys, all of that need to be taken care of as well. Yeast can be very difficult to get rid of! It is a beast!