Idk how to get out of my house + friendship issues

(16f) I have some friends but I’m having trouble with friendship at the moment. I don’t have my drivers test until September and it’s July now so I don’t have my own car or license yet. My friends make plans very quickly and last minute so it doesn’t give me time to ask my mom to drive me over. Also they want to go out to dinners and restaurants and I’m having major like major issues in public settings especially without my mom. My mom says just ask someone to pick you up and I’m like I physically can’t bring myself to do that. I feel I’m annoying people. In my town, they have these concerts at the park once a week and this is the last concert and I haven’t been to any of the concerts yet this summer. I wanted to go but nobody is giving me a clear answer to what exactly is happening. I feel out of the loop and I feel like once I leave town for college which is next month I want to move on even tho these friends are nice and supportive I’m just so embarrassed to tell them I’m having issues leaving the house