I don't want to sound but is this for real? What does it even mean that you met someone on internet who told you to invest in some unknown crypto trading platform? I just don't understand who someone can fall for something like that. Why should someone you don't know giving you suggestions? And especially, why should you even listen to this guy? Of course you've been scammed.
That's a pretty common scam tactic in which "female" contacts the victim, flirts with him for some time and then moves conversation towards "incredible investment opportunity on xyz platform".
This is just like a newer version of the Nigerian prince emails, nothing more, nothing less. I just don't get it, it's like if someone on the street asks you to give him $50 telling you he's going to be right back with $100, he just needs to get into his car to get you the money. Would people fall for something like that? At this point I would say yes.