Why did this guy act freaked out when I told him me and my husband are trying for a baby at the end of the year?

I got married last July and a lot of people at work have been asking me if I plan on having a baby. I pretend but I don't want children because I don't want mangerment to know or it's another excuse for them to never promote me not but I think it will happen anyway and I personally think asking someone questions like that is very personal and private in the workplace.

For this reason I've not told many people but me and husband are planning on trying for a baby whilst travelling around America in September.

I've told a couple close work friends but no one else. There's a guy i walk to on morning shifts called Nathan. It's pretty obvious Nathan has a thing for me as he doesn't talk to many people at work especially women and he always makes a big effort to talk to me and he'll talk to me for hours but acts really awkward and clumsy. He hasn't denied but he likes me either when other male colleagues have made fun if him for always talking to me.

Nathan respects nothing will ever happen and but I'm married and I'm not gonna be a bitch to him for being attracted to me it's normal and without sounding up my own ass I'm used to it and I don't really care anymore. I'm petite, blonde and blue eyed of course I'm gonna get male attention. Nathan is not a threat and is a very sweet man who just needs someone to talk to sometimes.

He asked me today if me and husband were planning on having a baby soon now were married or if I'm already pregnant as he's noticed I've been on light duty's at work a lot lately.

I told Nathan I'm not pregnant but I might be by the end if the year. Nathan went bright red in the face and said "okay I'm gonna leave now" and ran off. Nathan hasn't spoken to me since.

Is it the fact he knows I'm having sex uncomfortable for him? as I know a lot of men see me as like a virgin that needs protecting when I'm not just because of the way I look and act.

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Or was it the fact he relised Its never gonna happen with him because I plan on having a family? Which I think it was pretty obvious it was never gonna happen from the get go.
Why did this guy act freaked out when I told him me and my husband are trying for a baby at the end of the year?
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