So, I bought a laptop on ebay and i messaged the seller why i haven't received a shipped confirmation but they said that they don't go through ebay shipping and that they already shipped the laptop, should i believe them?

First, look at the seller's rating. If it's low, I wouldn't.

Wait for the laptop to come. Give it extra few days after the expected delivery date because it's "Christmas season" and all.

Ask them for the tracking number. If they say there isn't one,they're probably lying about shipping it.

No, Use your Brain. Browse to gather some knowledge about the product.

NO