House price difference in same street

Hello All I had an offer accepted on a semi detached house for around 420k. This has a orangery extension that was recently completed and the interiors ( wood floors, repainted etc) are all recently redecorated. We were excited to move in and the process is ongoing.

In the same street today a terraced house of a similar dimension but without the extension and the original decoration( carpet flooring, etc) but well maintained has come to the market for 345k.

I feel a bit confused. Am I overpaying for my house. I also noticed that the houses in the cul de sac at 425 range have been there for more than a month now.

Should I renogotiate 🥺