Ebay...to give or not to give....

So i know there are tons of ebay threads but i wanna see if my actions are justified.

I purchased some shocks and everything went fine. The electronic notification was done the next day. Notification was July 24. I waited until July 30 before contacting the seller, because the tracking thing said USPS never received anything. He told me the package was sent on the 24th.

I called USPS and they assured me nothing has been received on that tracking number. I gave the seller benefit of the doubt and waited...and waited...

I messaged him back on AUG 1st to tell him to contact his postal place to see what is going on and he refused. just said he was a "big business and knew what he was doing"

Yesterday...August 4th finally something has been recorded in his same state. So thats 11 days that USPS had it...and it didnt leave the state?
I called once again called USPS and they assures me the package was not received on the 24th

He is now calling me a liar when i confronted him today. Keeps saying "we are a big business and we know what we are doing"
In general his responses make me wanna punch him in the face.....or even a small child....
Am i justified to negetive feedback his @$$? can he negative me?....sorry im a negative feedback virgin

I WANT MY SHOCKS NOW