If they started manifesting after this bad moment with a friend, it’s likely your friend sent parasitic entities your way or perhaps what happened may have attached them towards your energy and space but these entities are by no means covered although some can be powerful. They CAN be banished but it seems like you are in fear and they feed off that which doesn’t help your attempts at banishing very well. Try banishing with intent because they may put up a fight during a banishment.
It also seems you’ve already tried many different attempts at it too. It helps if you can have a trusted friend assist you. Your will and intent are important.