Looking to try make some friends to make it easier for me with my social anxiety to go to one of the UK show in December

I've never been to a Concert, Gig, Live Show or even into a club before and really wanting to go to one of the upcoming Sabaton show in December however, it's a huge jump out of my comfort zone for me to be doing by myself so hoping to meet people to help ease my nerves going to, during and after the show. (Probably looking at the London atm show) My biggest concerns currently with London is; getting from the Train Station to the O2 (as I'm overwhelmed by the Underground), getting into the event itself, then figuring out what to do afterwards regarding getting back home ect, I think once I'm inside I'll probably be alright as I can walk around McM London Comic Con by myself (admittedly my friends were waiting in a queue to meet a celebrity at the time but still) just everything else is abit daunting 😥.

I live in Northampton and have been trying for months here and in other groups (including Facebook Pages) to try to see if anyone's local in the hopes of meeting up and maybe making some new friends with honestly little luck. I do take frequent trips to Coventry and Birmingham by train (planning my next trip on Thursday 13th November) atleast once or twice a month if anyone's in those areas too to hang out for a couple hours (still got my duplicate Stickers to give out also)

Just looking to try to actually make some friends and to hopefully get a clear idea if I'd actually be going to one of these shows or not.

Many thanks