Benzos with alcohol? I wanna know if I'm safe right now

okay so I (19F) took benzodiazepines in the morning around 8:30AM (it is currently 5PM)

I took abt 3mg worth of Alprox, I forget what the active substance in it is. 6 0.5mg pills. I had an important test in the morning and I wanted to relax a little.

however I am a raging alcoholic. I ended up forgetting that I took the pills and I've drank 1l worth of 12% beer during the last half hour.

THIS IS MY FIRST TIME ON BENZOS!!!!! I just got them (and yes, they are prescribed)

i also take venlafaxine, lamotriginium and methylphenidate daily. I've always drank with the previous three so I'm never too worried about them, but I hear that benzos have very bad reactions with alcohol.

what should I look out for? I don't know if I took a lot or not, but I don't feel like going to the doctor before I start having actual symptoms.

any help and tips are appreciated, thank you!