Where that comes from
The Qur'an names the whisperer, and names him as something that comes from outside and then slinks away. The report is the Companions describing your experience in their own words, and being reassured rather than warned.
Qur’an and Sunnah
مِن شَرِّ ٱلۡوَسۡوَاسِ ٱلۡخَنَّاسِ
against the harm of the slinking whisperer––
Qur’an 114:4
ٱلَّذِي يُوَسۡوِسُ فِي صُدُورِ ٱلنَّاسِ
who whispers into the hearts of people––
Qur’an 114:5
مِنَ ٱلۡجِنَّةِ وَٱلنَّاسِ
whether they be jinn or people.’
Qur’an 114:6
It is narrated on the authority of Abu Huraira that some people from amongst the Companions of the Apostle (ﷺ) came to him and said:Verily we perceive in our minds that which every one of us considers it too grave to express. He (the Holy Prophet) said: Do you really perceive it? They said: Yes. Upon this he remarked: That is the faith manifest
Sahih Muslim 132graded sound, sahihaynfull report
Translation: M.A.S. Abdel Haleem, The Qur'an, Oxford University Press, 2004.
What the research says
Radomsky AS, Alcolado GM, Abramowitz JS, and 16 others (2014). Part 1. You can run but you can't hide: intrusive thoughts on six continents. Journal of Obsessive-Compulsive and Related Disorders, 3(3), 269 to 279 doi
683 students at 15 sites in 13 countries across six continents. 93.6 per cent reported at least one unwanted intrusive thought in the previous three months. Having them is close to universal.