Can somebody send me an in depth URL on options

I tried to experiment with shorting (I made really long put using the wizard) DJT a while back. The price dropped and it showed a profit. The price dropped more and the profit disappeared.

At least two attempts, I have watched the numbers go the opposite direction from what I was expecting.

I am trying to backtrack months later to try and figure out what I did wrong. I understand the general concept but I haven't seen the math play out enough ways to get it to click.