New to table, no reads, raising T9s in early position isn't great. And sizing isn't great. $12 in a $1/3 is a little small, too. Not sure if it matters all that much, but when I play $1/3, I tend to default to $15 as standard open.
As played, OTT, bet. Your hand improved, and there are a lot of river cards that will be scary, esp any non diamond A, K, Q, J.