My address has somehow changed from http to www & I'm seriously confused

OK.

My site was https://thepopcorngirls.com – this is how I registered it both with wordpress & with Site Ground.

Anyway, I think it may be because I enabled Cloudhost which mentioned it needed to use www. to work & after that the site crashed, was a complete nightmare & ended up having to restore to a previous backup.

I didn’t even think of the cloudhost thing until today (Site Ground told me it was my theme causing the error or SEO plugin) when I noticed that under General Settings my site was now https://www.thepopcorngirls.com and this was preventing commentluv from working.

The novice that I am tried to change the address back to https://thepopcorngirls when my site crashed again, obviously. I don’t know how I fixed it but I did (go me). Think it had something to do with changing the site & home in myPHPadmin to https://www.thepopcorngirls.

So. It’s back working & I’m happy enough with that BUT my site is still showing as http//:thepopcorngirls.com in my cPanel and on siteground & was wondering if
a) it will cause any repercussions long-term and
b) if I change the domain to www. will it cause a whole new crash?

I’m seriously new to this & my head is spinning so I’d be grateful for any help I can get ??

Thanks x