Boyfriend texting unsaved numbers?

I'm really worried my boyfriend is being unfaithful because whenever I'm with him he always text unsaved numbers and today I was at his house with him and some unsaved number texted him asking him where he was and sent 4 or more messages and he replied at the movies which he wasn't. Is this a red flag or am I being paranoid? Thanks
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+1 y
He also has like almost 700 unread messages
Boyfriend texting unsaved numbers?
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