Trying DXM gels in 2 days?

I am going to a bush party in 2 days, i am 14 and weight about 120 pounds and am 5'5 i am planning to take about 10 15 mg pure dxm gels(robitussin) so about 150 mg of dxm. will this be enought to reach plateau 2 and are there any concerns about that amount, how long will it last and should i drink or smoke(pot) during the bush party.... also i have never tried a hallucogen b4 except when i was on codiene in the hospital, what can i expect from a halloucgen like dxm, and will i be robo waling at this dose because there will be cops out that night and i dont want to look like bait??? thanks if you can answer most of these questions or all appreciate it :D :D :D :D :D