Hey guys, I'm a long time lurker as i'm sure many of you are. Recently I've just been trying to improve my game especially with hotter girls. Anyways today I was in a pretty good mood, and of course in the summer you're just a little more cheerful than usual. Out of the blue I decided to drive over to the mall and just walk around and chill out. So after exploring a bit, I go to the food court, walk up to some deli and order food. The cashier was really cute. I decided to just be pretty relaxed and to be friendly. I ordered coffee, and when she asked me how I liked it, I said black. She was surprised and we had a little convo about that, in which I made her laugh a bit. Then after some time I got my food and while I was paying she laughed some more. In my head I was thinking this is good; she seems to be enjoying the conversation and so I told myself I wanted to get her number before I left. I got my food and while I walked away she said alright see you. So i ate my food, and as an excuse, went back to the deli to get some orange juice. When I got back to the deli she looked happy, in fact, almost excited to see me again. This is where I'm confused. I made her genuinely laugh again, and proceeded with this: "Hey I don't know if this is too forward, but could I get your number? You're cool and I'd like to hang out with you." She smiled and was still slightly laughing but was like i don't know, and I said, "Do you have a boyfriend?" She said yeah and then we exchanged names lol (I know I probably should've found out her name first). But I took it in stride and remained confident. I said well hey I have nothing to lose, and said it was very nice to meet you. I walked off feeling relatively good, but still a little perplexed. I thought it was going so well. So where did I mess up here, if I did at all? Was it when I asked her for her number with the "Hey I don't know if this is too forward..." bit, or what? Should I have been more dominant about it? Thanks guys, I'll be looking forward to all of your suggestions. Peace brahs

Tldr; Saw girl, approached, made her laugh a lot, but didn't get the number. Suggestions?