Am I weird for not minding too much?

My boyfriend asked me if it was okay if he traveled to Hawaii with a friend for several days to which I said yes. Then later he tells me that that friend is a female. (He also said that he didn't want to hide that fact.) He was worried that I would be upset or mad at him for that, but I said that I was okay with it. I think he still didn't believe me at first because he kept trying to defend himself. But I told him that I really didn't mind and that I'm not the type to get jealous or upset easily.

Am I weird or not normal for being like this? Should I be worried? I feel like it's more common to care or even be upset about it.

Maybe I'm like this because I don't know who this female friend is, or I'm just normally a very understanding person. If I were in his shoes I'd probably want to do the same.

Nonetheless, I'm still thankful that he told me.

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+1 y
Kind of random side note, but why did GAG change boyfriend to boyfriend?
Updates
+1 y
I meant B F to boyfriend (it did it again).
Am I weird for not minding too much?
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