If you switch from one alcoholic beverage to another, you're still putting alcohol in your body and will continue to be affected by it. It takes the body, on average, an hour to metabolize an ounce of alcohol. This rate varies depending on the individual's gender, weight, and food consumption.
People are friendlier when they've had too much to drink.
While they may appear friendlier, in actuality alcohol has just depressed some of their reactions. They may be louder and talk and laugh more, but since their judgement is impaired they may also take more risks, do dangerous things, and be more hostile. If you think you've had too much to drink, eat something. If you think you've had too much to drink, you probably have. The best thing to do is to stop drinking.