Blackout advice

I (24 F) recently at a sporting event was drinking in the parking lot had some pink Whitney shooters and a truly and a half went on to get a cocktail and about halfway through that drink I aggressively and suddenly blacked out. I’ve never really blacked out from drinking and I’m definitely not a casual drinker by any means. My boyfriend thinks the cocktail I had was spiked but I ended up in the ER from being so incoherent. I am really struggling with knowing if I was slipped something in my drink or if I brought this on. I’m reevaluating my relationship with alcohol but this whole event feels really off and was really scary and I have never been so blackout drunk and I’ve consumed more previously.