From the FAQ:
Your Average Score is the weighted average of
your ten best out of your last fourteen stroke play scores (Practice
rounds are not included). Your most recent scores are weighted more
heavily to ensure there is no "sandbagging".
In your case, you still have a high average because you don't have 10 rounds under your belt yet. Since you've only posted 2 scores, it's using 150 for the scores that aren't there yet.