It's very hard to answer what the public "thought" about anything if there wasn't careful study of it at the time. There were no polls done on the Japanese public between the use of the bombs (August 6 & 9, 1945) and the end of the war (August 14). There was not even that much research done on Japanese public opinion regarding the atomic bombs after the war. I have written at length at the difficulties of knowing "global reactions" to things like this.

In general, accounts of the Japanese public opinion in the late war emphasize that most were well aware that the war was not going well, even though they had very limited accurate news information. The fact that the US was bombing Japanese cities with impunity was obvious to them, as was the fact that there were critical shortages in food. But after over a decade of military rule they were largely not in positions to voice any kind of public or even private dissent. Many report being shocked when the Emperor announced surrender, because they felt the war had been for nothing, in the end. But again, these are impressionistic responses, not careful surveys.

We have a little data on Japanese morale, and attitudes about the atomic bombs, from 1947: see here.