I have an uncle that has this funny habit of answering the door before you ring the bell. That sounds impressive until you learn how many times a day he opens the door and no one is there. He's schizophrenic. The cost of increased sensitivity is a higher false positive rate. If there were no drawbacks, evolution would have given us heightened senses 100% of the time.

I'm not suggesting you had any sort of psychiatric issue. I'm sure your increased sensitivity was very real and very grounded in realistic expectations of reality. But, are you sure that there were no false positives that came with the heightened sensory experience? Did you ever check that the thing you recognized as a garage door opening down the block was in fact a garage door opening down the block? Could it have been some other subtle sound you normally don't pick up on?