Is it weird that I'm using dating apps for validation purposes only?
It depends on why are you using a dating app in this manner?
I'm using it to know if I'm fine with being single
It's understandable to want validation from others. Doing so through dating apps though is shallow though. You never know if someone is being truthful or just wants a date.
I don't care, I know myself and I'm happy.
As long as you don't lead anyone on while using the app, I can see how someone would want to use it as validation on their looks. But, if you start talking to someone and don't plan on dating them, be upfront so they don't believe something is going to happen.