Too old for a promise ring? Is it pointless?

I love my bf and he says he loves me too. He expresses it in his version of love which is time and money but to me thats nothing. I see love as long talks at the park not spending money. He never shows me in the way i see love so i feel insecure on how much he loves me. We never discussed or considered marriage, we are both 19 but I want a promise ring just to feel reassured that he loves me as much as i love him and that we are both committed to each other. Is a promise ring just for teens like high school kids? Is that childish? I googled it and all guys just diss it and call it useless garbage