Are AncestryDNA tests worth it? (Family secrets)

I found out last year that my great-grandfather ran off after having my grandfather and his older brother, then disappeared without a trace for five years before coming back and having three more children with my great-grandmother. Nobody in my family talks about this and it has me wondering if he started another family somewhere and then came back like nothing happened.

My family has a bunch of skeletons in the closet— I have no idea where any of my father's family comes from, what anyone did for a living, how they all ended up on entirely different corners of the united states... My father said he was born in New Mexico and lived there until he was 4 when my grandfather suddenly packed the whole family up without notice or a chance to say goodbye and moved to Maine— no job in place, no house, nothing. I don't even know where my grandparents were born. I've tried to ask questions but the topic always gets changed immediately which just fuels my curiosity even more!

My whole dad's side is a bit ethnically ambiguous but all speak just English. My mother is fully white and knows her whole

familial history as my grandmother was super into family trees and tracing heritage. When I was a child I looked super white but as I've grown older my features have darkened and people have started asking me what my ethnicity is and I have to say "I don't know!"

Would a $100 DNA test be worth it? I'm so curious and want to have some heritage to explore and hold onto if I can. I'm also afraid to open the can of worms that is possibly having secret family members???

Me and dad when I was a baby

Me now (bad pics but only recent ones without a mask covering half my face)