second-guessing

Short definition from Wiktionary

Noun

1. 1
   The act or habit of vetting, evaluating; criticizing or correcting, often by hindsight, by presuming to have a better idea, method, etc.
2. 2
   The act or habit of anticipating or predicting someone's actions or thoughts by guesswork.

Verb

1. 1
   present participle and gerund of second-guess
2. 2
   present participle and gerund of second guess