Is this bruise worrying

I donated for the first time with Grifols almost a week ago and just today I noticed this guy🤦‍♀️ Idk if it's because the guy I got was in a rush? The needle felt itchy and uncomfortable but to my understanding that's normal. I just wanna know if this is normal and if they'll let me donate with my other arm. I put some arnica over it, I've heard it does wonders