Is what I feel of distress and escapism when committing sins a deception from Satan, who deludes one into thinking a sin has occurred, or is it a true feeling seeking forgiveness if the sin has indeed occurred, and is this type of satanic deception possible?

The reference for knowing what is forbidden (haram) is the Sharia evidence from the Quran, Sunnah, and consensus (Ijma'). These are received from revelation, so Islamic knowledge (al-ilm al-shar'i) is the only way to know whether an act is a sin or not. Repentance (Tawbah) is essential for the servant in every state; it is the first, middle, and last of stations, and it does not leave the striving servant until death, because one is never free from sins and shortcomings. Abandoning commanded good deeds is more significant than repenting from prohibited evil deeds. The expansion of one's chest (inner peace) may be a sign of the acceptance of repentance, but the servant cannot be certain of its acceptance. One must adhere to repentance and seeking forgiveness while doubting one's own repentance, and not pay attention to the whispers of Satan.