Middle finger into Palm is sore & hurts. Dr said trigger finger. Could it be infection instead? No swelling or redness. No injury to hand. Only middle

Not likely infection. Trigger finger is more common (especially in the dominant hand) in a healthy individual with no history of trauma, no redness, swelling. There is often a mass that can be felt and move with flexing and extending of the finger. If infection is present a present usually doesn't tolerate moving the finger. Trust your physician. If you have doubts "see" another physician.