I think there are two dimensions of Qabr. Like martyrs are عند ربهم they feel close to Allah and pleasant breeze of Paradise. The other dimension is like a horror movie with real horror. The Hadith of sandwiching of qabr with pressure shows that the pain will be real. The real question is not to fully understand it but to know what to do about it. According to narrations reciting Surah Nisa every Friday will protect from the collapsing of grave. Another narration advises keeping yourself pure from major and minor impurities. Another narration talks about making believers happy. Another narration recommends Surah Mulk every night. The conclusion is that our actions here determine our future whether eternal horror and trauma or eternal bliss, happiness and salvation.