Yes, now you can buy - its a deep now. After 1 month bitcoin will cost a 19000 again - you can be sure. So dont be slow and dont miss that moment.
I agree that you are looking at a good buying opportunity if you have cash or Fiat on the sidelines. I think we are in for a rocky 2 to 3 more days then expect btc to go sideways a bit and make its way back up.