1.d4 e5?
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It's called the Englund Gambit, but that was just ... awful. What rating was your opponent?
Englund is incorrect. With correct play, white wins. Therefore, GM's don't play it.
However, you need to know some black traps.
Mandelshtam
Yes, the Englund Gambit is frowned upon as dubious, and it is unsound. However, there is some danger, as you need to be on the lookout for traps.
When I saw 1...e5 i thought at first it might be an opening I've never seen before and might get into a trap, but after some consideration I took it and it turned into a foolish game. This shows moves that shouldn't be made.