"didn't know what I had till it was gone" is a standard phrase meaning "I didn't realize how much I appreciated it till I didn't have it any more"
"They took all the trees, put 'em in a tree museum / And they charged the people a dollar and a half just to see 'em / Don't it always seem to go / You don't know what you've got till it's gone / They paved paradise, put up a parking lot" -- Joni Mitchell, Big Yellow Taxi https://www.youtube.com/watch?v=xWwUJH70ubM
I thought it was normal.
"didn't know what I had till it was gone" is a standard phrase meaning "I didn't realize how much I appreciated it till I didn't have it any more"
"They took all the trees, put 'em in a tree museum / And they charged the people a dollar and a half just to see 'em / Don't it always seem to go / You don't know what you've got till it's gone / They paved paradise, put up a parking lot" -- Joni Mitchell, Big Yellow Taxi https://www.youtube.com/watch?v=xWwUJH70ubM