What is the ruling on praying when one presses their head down severely during prostration due to obsessive whispers (waswasah), feeling a heaviness after rising from prostration, and not repeating the prostration?

The cure for waswas (whispers/obsessive thoughts) is to ignore them and not pay them any attention. What is obligatory in prostration (sujud) is placing the forehead on the ground. Some scholars mandate pressing down on it, by which they mean enabling the forehead to be firmly on the ground, not exaggerating or being overly strict. Al-Sawi states in Bulghat al-Salik that pressing down means resting the head on what one prostrates upon in such a way that one is not considered to be holding it up; mere contact is not sufficient. It does not mean pressing the forehead onto the ground so hard that it leaves a mark. The questioner's prostration is valid and does not need to be repeated. One must be careful not to be overly strict (tanattu’) or fall into waswas, because giving in to them leads to great evil.