Mystery

I have been in Tecomán, Colima yesterday and today I visited the archaeological site La Campana i Colima. In Tecomán I took a few photos and av the archaeological site I took lots, but when I tried to upload them on my Google account I could not find my photos of these two days, even they were there earlier, when I checked the quality of it. The camera has no WiFi, though it could not have been hacked. I am just wondering, if it is possible, that the photos disappeared, because the battery run out of charge or maybe by the heat today. I also charged my cell phone, which were getting warm and close to the camera. On the other hand side, if that would matter, I do not understand why not (luckily) all photos were deleted.

Has someone of you an explanation for this mystery?