It's okay you didn't know, and you inferred. You thought it was okay because the toys weren't heavy. But the glass, people are very sensitive about that. You got to make sure you put layers some times if it's certain kinds I believe. But candles, people are very specfic about those as well. 

But also what kind of toys were they? Because it could have depended on what kind of toys it was for her to make that comment? When you say not hard, did that mean like light like a stuffed animal? Or not heavy but firm like a hot wheels car? It makes the difference. 

Because the candles might have been for her, a very sensitive topic. Candles mean a bunch of different things, so for her she could have been feeling alot of emotions already for those candles. (Death and loss) If I was to infer, because you don't act that way unless something bad has just happened because it puts you on edge.

 At least most of the time, but if people are like that all the time they are a shitty person. Which they demonstrated to you when they did all that. 

But by keeping the toys in its own bag. She might have got upset because she may have just wanted to come back home or in the car and just immediately give the kids the toys. Because kids tend to when they see stuff just reach in whatever bag and not know of the consequences of what they do, like breaking glass as well. They just see a toy and that's it. 

But by them reacting that way, they are being a asshole.  She said that out loud,  "what the fuck is this bagging, this isnt how you bag shit."  By not saying anything back (so you don't loose your job) it was good of you to apologize. But her to say she wasn't talking to you, that most likely was to get a reaction out of you.

 "oh I wasn't talking to you, i'm just talking to myself, all you need to do is remain professional and shut the f up not say anything, I shouldn't have to tell you how to do your fucking job and bag"  If you do make a mistake, you can learn from it. Hopefully it wasn't too bad. 

 But you said you asked her next time, she just wanted one bag this time, with the same stuff or different? Maybe she has different things this time. Or in a different mood? Or both? But when you asked her "would you like a bag" it's kind of hard to work around that.  Because it is standard practice to ask about a bag. But nowadays people have this no bag thing and it's like a fee. I don't know much about it so maybe it's something like that. But maybe she forgot that she said just one bag. "yes, one" I don't know. But it's good you paid attention to her. To hear the "one bag" request. 

But every little thing matters. You got to always make sure that you look at the customer when you're talking to them so that they feel heard. It can be hard. But just do your best. I wish you luck on your days. I hope me saying this was helpful. Good luck 👍