Fuck man, that is a HIGH dose! You'll probably just feel real drunk and pass out. A recreational dose for someone without a tolerance is 450-600mg. If you takes doses too high, like the dose you listed, you won't feel the effects...just get dizzy, drunk and pass out after an hour of effects kicking in. For the full effects what you want to do is take 600mg max. You can always redose
Possible effects include feeling floaty, objects becoming enhanced, colors becoming brighter, partial tracers, a feeling of being on a psychedelic, desire to socialize, decreased inhibition, intoxication, blurry vision, strong empathy, euphoria. Almost like your on MDMA just without the powerful stimulation and dilated pupils and the experience isn't as strong. Effects are milder.
These are all "possible" effects. You may experience some but not others. But if you take 1500mg you won't be able to experience the majority of these. The effects take long to kick in. You should start to feeling the effects after an hour or two. Duration can be up to 12 hours "or more" depending on the dose. At a moderate dose usually it'll last about 8 hours