This is a pure symbolic interpretation, and how I would interprete it if I had dreamt it.
Symbolic messages in dreams often are about growth. A house - any house - is an alternative representation of you. A father in a dream stands symbolically for the part of you that is authoritive and protective.
Exorcisms are performed when people are said to be possessed by a spirit that makes them behave in a way they normally would not. Possessed people are then believed not to be responsible for their own actions, since it's not them doing it, but the spirit making them do it, nor do they even have control over their own bodies. So being exorcised would then indicate that you are liberated to have control and responsibility over your own life again.
Being sprinkled by holy water is a protective symbol, a blessing and also cleansing. So, combined with the exorcism would indicate that along with regaining control and responsibility, you also get a blessing, protection from harm and clensed from your faults of the past events. It's almost as if your father is saying, 'time to stand on your own 2 feet with my blessing" ?
You mention how the Holy Water burns your arms. Arms are what you use to reach out for someone, to care for someone, to hold them, to protect them ("arm yourself"). While fire may be a destructive force, I see it here as a clensing symbol too, especially one where you are being transformed.
Hope that helps
