"i think we might need to get you to a hospital..." - @quiitecontrary
Absolutely not. While this stranger, the rare good Samaritan in Gotham, means well, it wouldn't take the sharpest eye to notice and have questions about the myriad of scars along her body. Questions she doesn't have any good answer to. One look at a drug test, and they'd "suggest" a rehab program that would steal all her time from the church. Crane would be furious, and he has enough going on right now without that wrench in the gears.
But, the fastest way to make someone think you must go to a hospital is to insist that you don't. Especially if they're prone to assuming that they know better than you. And good Samaritans often assume that much when blood is still pouring down your face, but it'll clot soon enough.
"No, I'll be alright. Nothing is broken." No broken ribs, at least that much was true. Riley knew what that felt like, and this wasn't that bad. She could still talk after all. No, there were just going to be some ugly bruises for a while.
She needed to make the good Samaritan feel useful, otherwise shed never leave her alone. They need to feel like they helped someone. It helps them sleep better. "I just need to get home. Maybe you could call a cab?"