Pending vs Recieved Money (Ebay to Paypal)

[cholby111]

OK id like to share an experienc ive had before where i sold an item and the buyer refunded the purchase leaving me out on the item and the money.  Im not an experience seller on the internet and trying to comfirm a few things.

I currently sold an item on Ebay with paypal and the buyer purchased it but the money is still pending and i dont want to ship the item and the purchase be refunded on me. The item is pending for 21 days? is there a way I can make this process any shorter? 

Also how do I know that the money is completely safe from the buyer to refund ever? if the payment goes through and goes from pending to into my balance does that comfirm that the money is securely mine? I ask this because I thought the money was securely mine last time and I ended up getting refunded on.

Maybe its because I sold an item over someone that i thought i could trust through an invoice on paypal?but the money showed up on my paypal so I thought the money was secure.  if the money is from ebay purchase and the pending transaction goes through is that safe?