Does the repeated hindrance from going to the mosque to perform Fajr prayer in congregation, due to passing wind or another impediment, despite prior preparation, mean that God is angry, or is it a sign of weak faith?

The reward for congregational prayer is written for the one who misses it due to a valid excuse, and it is hoped that he will attain the reward of the one who strives to attend. However, it is feared that this might be a form of waswasah (whispers from Satan), which he must repel. He should strive to take the means to wake up for the congregational prayer. If he is unable to do so, then "Allah does not burden a soul beyond its capacity" (Quran 2:286), and there is no accountability upon him for that which is beyond his ability.