Lightroom classic cc became extremely slow within two days

It's not the folder. Brushing and spot healing are known to cause Lightroom to slow down. The more you do, the slower it gets.

Some things you can try:

1. Turn off the GPU acceleration. (This may make some things slower, but it should speed up the brushing and spot healing)
2. Do the brushing and spot healing as the next-to-last editing step; and as the last editing step turn on lens corrections and transforms.
3. Do the brushing and spot healing in Photoshop or Photoshop Elements, where it will be much faster
4. Get a faster CPU.

You might need to tell us a bit more about

- Your exact version of LR (numbers, not latest or alike)

- Your OS and version

- Your hardware (CPU, RAM, GPU type, disks where catalog and photos reside on)

I just found out that it is specific to one folder. Could it be possible that if I highly edit several photos (in this case in the folder there are 6) it bugs and slows down?
I exported the flagged photos (15 in total) of the folder to jpeg files and opened it in Lightroom CC (not classic cc) and it performed fine. But when I export the same flagged photos original instead of jpeg and open them in Lightroom CC, that program also slows down when trying to edit the target photos.