Who do you think is right?

Our son is two years old and when I tell him he's not supposed to do something and he gets sad I don't always comfort him right away and my husband think that's wrong, that I should never let him cry. I'm talking about less than a minute here. It's usually when our son does something that needs fixing, like if I have forgotten to put the dogs food and water bowls up and he pours all the dog food in the water bowl, I tell him no and that he's not supposed to do that, which he knows. Then he starts crying and I pick everything up, then I pick my son up and distract him with something else. Am I a bad mom for doing this? Should I comfort him right away? I'm not doing this all the time, I only do this when it's something he knows he's not supposed to do and I need to fix it. If it's something new or something I don't have to fix, I usually pick him up right away. I'm always explaining why to him, even though he doesn't quite understand. However I feel like if I'm always picking him up and comforts him when he gets sad, how will he ever learn something isn't okay? Isn't it okay for them to be sad for a few seconds once in a while? I don't let him cry as a punishment though. I need advice.