Your first two deaths are "free", as you said. Basically, they are guaranteed resurrections. After that, every time you attempt to resurrect, you have to draw from the "bag of chance", as detailed in the rulebook. The bag contains 10 stones with 1 black stone for each of your deaths after the first 2, the rest are white stones. If you draw a white stone, your rez is successful, otherwise you "perm" (or suffer Permanent Death).
Your risk of death is related to your character's involvement in dangerous activities and how much the other characters support you. If you're a front-line fighter, you're likely to be dropped to -1 Body many times, but you're also likely to be propped back up by healing. It also depends on your chapter. Some chapters have more deadly plot lines currently going on, so maybe there will be one person rezzing in a weekend, or there may be 20 (or more).
Overall, I'm going to say it's doubtful that you will Perm on your first weekend. If, by chance, you are an unusual case, you can always NPC the rest of the weekend and use the time to work on your technique or try different play styles (healer, c-caster, fighter, rogue, alchemist, templar, scout, etc.) to find one you like for your next character.
-Luke