Why has he got shyer with me all of a sudden?

[Emz19]

There's this guy and we have a crush on each other (I don't think he knows that I like him). He's local and I occasionally bump into him in the street. When I do bump into him (which isn't very often), we have nice little chats. I wrote to him on WhatsApp a few days ago and asked him round to my home for tea. He responded and said he'd like to come round and he asked if I could confirm a time on the day (which I did). On the day (Thursday), I texted him suggesting a time and he didn't bother to reply. My message came up as unread but I'm sure he saw it because if he was expecting a message from me that day, surely he'd check his WhatsApp to see if I had written. Anyway, the message was marked as 'unread' the whole day. He wrote to me this morning saying "I missed this sorry" and that's it. I'm guessing he's apologising for not 'seeing' the message in time. I think he lost his nerve. He's got a lot shyer with me. Me and him were having nice chats when I bumped into him but now he seems too shy to meet up with me. I can tell he's got shyer just by how he is when I message him on WhatsApp. He was never this shy before. Anyone knows what might be going on with him?

[Wise4myage]

Guys can tend to become shyer around the girls they are into. You need to make it known that you like him, so try flirting with him.