took a tab and 0 effects

i took a tab 1.5 hours ago and i dont feel anything yet. I felt something in my chest and a little of anxiety. also i dont know the source of this lsd since i got it from a rave last saturday(some shiva blotter). should i take more? EDIT: 2.5 hours later and still no effects, i will try tomorrow with another tab and some hash, what do you guys think?