CRUSH TEXTING FAILLL. PLEASE HELP ME!!!!

Okay so I’m gonna try to keep the backstory short but last week I went to a health resort with my best friend. They had a teen program we both did. We met a really cute guy. He’s a few years older than me and super nice, cute, and smart. His sister was also there(she’s great too)! I only stayed there for one week, but everyone else stayed for two(so they just left yesterday). He found out that I had a crush on him on my last day, but just acted normal. He texted me on Wednesday , and it turns out that he fell there and broke his shoulder. I texted him backs and we had a short exchange AND THEN MY FREAKING PHONE GLITCHES. So I ended up getting the same text from him over twenty times. Ugh he hasn’t texted me since, I haven’t texted him either. His sister said he was awkward around girls(he goes to an all boys boarding school). She also said that I was kind of his type. So I think he’s embarrassed about the text fail. I really want to text him but don’t know what to say. Do you ladies have any suggestions? Even if he doesn’t like me I still want to be friends with him and his sister. I also don’t really know what to text his sister(or if I should). I would love to get some advice about what to text him.