Is a decrease in hair thickness, rather than just the amount falling out, also a sign of hair loss?

Lately, the amount of hair falling out when I wash it doesn't seem to have changed much, but overall, my hair feels weak.

Especially when I touch the top of my head, it feels thinner than before, so it's bothering me for no reason 😥
Even if the amount of hair falling out is not significant, if my hair thickness continues to decrease, would it be a good idea to get a hair loss test?