You probably won't get high the first time. Depending on the quality of what you're smoking, you may start to feel what I call "fuzzy-headed." This can happen when you're smoking low-potency cannabis, and it's not the same as being high. It took me six attempts to get high, and the sixth was a very high dose. I sincerely doubt you will experience any paranoia the first time you get high. The first is usually blissful beyond anything you've ever experienced.

As for what it feels like, if you DO get high, you will know. At first you will just feel very relaxed and pleasant. Then the feelings of euphoria will become more intense. You may find that you have a greater appreciation of everything around you: friends, music, movies, and life in general. You may find you're thinking about things in ways you never have before. Your thinking may also be disorganized, and you might find everything humorous. Your heartrate will probably increase somewhat, but this is normal and nothing to worry about. You may even start to hallucinate if you have a very high dose (I did my first time). If you do, just enjoy the trip. After one to three hours of feeling this way, the high will start to diminish slightly and you will probably get hungry. Food tastes absolutely delicious. Treat yourself to something tasty. After another hour or so, your head will get more cloudy and you will probably start feeling sleepy and sedated. You can toke up again to avoid the sleepiness, but it will come on more heavily at a later time.

The most important thing to remember is to relax and not worry. Just enjoy the experience. If you don't get high this weekend, don't worry about it. Just try again sometime, and eventually you will get high.

As for how long it takes to get sober, you will be pretty sober five to six hours after smoking, but you will probably be sleepy. If you smoke in the evening (which is what I recommend), you will sleep wonderfully and when you wake up the effects will mostly be gone. You may feel slightly fuzzy-headed the next day, but it's not unpleasant at all. In fact, I often experience a very pleasant afterglow well into the next evening.

Anyway, I hope this helps. Good luck to you and have fun.