Shoud I continue trying?

So I have a big crush on a guy who is 3 years older than me. I’ve texted him several times and at first, he was very kind and friendly. I tried texting him a week ago, and he is treating like a child and I know it’s because of our age difference but I don’t want him treating me like a child.I also feel like he is starting to get annoyed by me texting him. I really like him and would want to know about him more but, I don’t want to annoy him. I don’t want to give up but, I feel like this is hopeless :((