Get your DEVELOPER to the right temp. It may be ideal to have all your chemicals and wash water at exactly the same temperature, but don't fuss too much if it isn't. My darkroom is an outbuilding. I only have cold running water. I don't try to warm it up, I just wash for longer. I don't bother warming or cooling my fix or stop either, unless it is unusually hot or cold.
Your images look great for a first try at developing. Congratulations!