Thanks! It's interesting how some artists suggest keeping showers minimal or not using direct spray at all and other suggest blasting the new tattoo with hot water for 5-10 mins. I've even heard of taking a hot bath immediately after. I believe it's a traditional Japanese method?
I'm very white as well and looking at the spots done with white, I can't tell any difference from it and my skin tone. Looking back, I wish at the very least I asked my artist to work with negative space. I think it would have rendered the same result lol.
Do you have any color in your tattoo? A lot of times colors are mixed with white pigment (titanium dioxide) to make them brighter. If that's the case, I might not be the titanium dioxide that is the issue. If you only have black and white, I guess it's possible you're having a reaction. Either way, going to a dermatologist and explaining your symptoms couldn't hurt.
I too have white in my tattoo and I'm regretting it. I'm actually regretting getting color at all for all the complications it introduces with pigment. If I do get any tattoos in the future, I'm sticking to black only.