Feel/Felt

[RedWood]

Long time back, I had an argument with one of my friend, regarding usage of word "Feel" for something happened in the past. Here goes my question:

If something happened recently, Can I say

I feel so sad for what you did on that day.
or
I felt so sad for what you did on that day.

What is it, in case if something happened in the Past (I mean not recently)

I have used the word "Felt" (in second case) which he reckons is wrong. Could someone correct me please.

Thanks.

 

[AintFoolin]

when the event happened does not matter, only YOUR CURRENT state

are you currently sad at this moment? then you feel sad

did you feel sad in the past? then you felt sad

"I felt sad when my dog died" (implies you've gotten over it by now)
"I feel sad that so many people died in WWII" (event happened a long time ago, but the feeling is current)