Did I really mess this up, really need advice?

I was 18 and working at a grocery store, there's a girl I met that was 17 and started working there a short while after I started back in the Spring. We immediately clicked, we would get along so well and I also started developing a huge crush on her. So the second time I saw her, I asked her for her number. She giggled and smiled and gave it to me. We would text a few times a week throughout the Spring months. We went out for ice cream once and she called me a gentleman and told me we need to hang out again. She quit her job this summer cause she was going on vacation to her lakehouse and then starting college in the fall. We texted a lot while she was on vacation, but when August rolled around I texted her and never got a response, texted a couple weeks later and same thing nothing. My IPhone has had issues before with Imessage so I don't know if that's why, haven't received a text since July in any event. It's October now and I found her on Instagram. I followed her yesterday night and this morning I happened to click on her profile and she wanted to follow me, I was so excited I'm not sure if I hit yes or no, and I was kinda in a rush. A few hours later I checked and I don't see her in my followers. I want to inbox her but I don't know what to say or even what picture I should take to start the inbox conversation, please help!

Take a silly picture or just a picture of your dog or the floor. It doesn't matter, and then ask her "my finger slipped when I was accepting your follow, I meant to accept, did it go through?" and if it did then say that you miss her and if it didn't then ask her to request again and then say you miss her and it'll most likely just flow from there. Don't be worried, you're probably over thinking it.

Maybe she was really busy or her mum confiscated her phone so she can't text you during her vacation. If she request to follow you and doesn't appear in your followers list then you may probably or accidentally click 'no' instead of 'yes'. If you really want to talk to her again, don't let anything stop you & just inbox her. Maybe she'll appreciate your efforts. Best of luck bro