Is my manager interested in me?

I (33F) am interested in a manager (44M) at my workplace, the only problem is; I am not sure he is interested. He's obviously a manager so compared to a coworker he would have to tread more carefully but how can I tell? He's really nice and funny, a bit annoying at times. We message at work a lot; sometimes work, sometimes random personal stuff. He remembered my birthday and when I am not having a good day he notices. When he comes to my office (not often once every 3-4 months) he will always come and see me to say hello an good bye, he even asked if I was at work once because he couldn't find me (I was in the bathroom lol). Are these signs of a guy interested or is he just being friendly?

Is my manager interested in me?
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