Spliff seeds amnesiac auto (My first grow ever)

After my cat pissed on my seedling in the last update, growmies on reddit advised me to heavy water which i did with distilled water on day 11. Now it's day 23. The soil did not completely dry yet even after 12 days!! Also i had an ongoing issue that leaf tips are turning brown since the day of the cat piss incident. The browning started from bottom leaves to upper. I cut those tips now as you can see, but the browning doesn't seem to stop. Idk whether it's the cat piss or the overwatering that is causing this browning🙁