It doesn’t matter whether you were a newbie or from old school. There's a saying, "If something is too good to be true, there must be something wrong". $300 return for $100 in 3 days exactly sounds like this.
Also, you could have been scammer with fiat money, or different e-money. That's the same thing. It's nothing to do with bitcoin. There's no certain coin/currency for scammers.
Have a good journey with Bitcoin.