Nickel allergy and sunscreen?

Hello.
Long story short, I have recently been diagnosed with contact eczema, or allergic contact dermatitis. My main symptom is the rash around my eyes. I will be getting the skin patch testing in November to pinpoint what is causing it, but after hours of research and also my own common sense, I'm about 97% sure I have a nickel allergy. How did I come to this conclusion? One, a ring I used to wear not too long ago would always cause very itchy and red bumps on my finger. Did I think anything of it? No. Two, I have 8 ear piercings, that I usually wear earrings in all the time. (just inexpensive studs) My piercings always itch, crust, and bleed. Did I think anything of it? No. My legs have recently become very dry, itchy and scaly, and I constantly break out in hives (only on my legs). However, the skin is only scaly and itchy where I shave, but not in my inner thighs, etc.

What do these all have in common? NICKEL. And I think that is also the cause of my eyelid eczema, because it turns out that there is actually nickel in iron oxides, which is in my face powder, eye liner and mascara, and also my eyelash curler.

Which brings me to the main question of this post.... is there also nickel in titanium dioxide and zinc oxide? I know these ingredients are in sunscreen, and I really want to be able to use sunscreen without worrying about my (potential) nickel allergy. :/ This is very urgent because I spend a lot of time out in the sun and I want to protect my skin.

Any input is appreciated!