Can I still be high the next day?

Let those flashbacks happen and relive those moments, that is the normal way a brain works when it wakes up dreaming. Not focused? You are having flashbacks of times when you were not focused, you were high, you were in a dream state and you will stay in the dream state. That is how weed works. The weed nowadays is big squishy buds that smell so good and they are so potent. BTW, weed is not illegal in 20 states. Weed is just like alcohol. It is a smokeable alcohol. You were having a hangover. With alcohol, the hangover is headaches. With weed, it is flashbacks. How long will it last? Some of the flashbacks may be bright and exciting enough to want to make another moment and you may not want it to stop. Weed may charge your brain in areas that have never been charged, but that is the danger. How long will it last? That would be up to you because weed stays in your body for awhile. You will have decreasing effects for at least 2 weeks. See, flashbacks are normal. Weed makes the flashbacks brighter, more colorful, more interesting because you can pay attention more to what is going on in your head. But that is the other side of the coin. You have to have knowledge in your brain of how things work and if you do, you will never be bored.

It is also possible its is still having an effect on you. Of course. Its your first time. Its bound to do that.