Dropping a grade

I've put Northumbria as my first choice and the course I've applied for requires 120 UCAS points, I know it doesn't really sound like much but I've just put my deposit for accommodation down and now I feel like I'm not gonna achieve the grades I need - if I drop one grade would I still be able to get in or be considered?
Might sound like a stupid question but I'm p worried ha

They would consider you, but it depends how many other students meet their offers. If they have space for 100 students and they have 100 students that meet their offers, all spaces are full and they can't take you. But if only 99 meet their offer there's a chance you could be accepted.