It may be worth getting one of your lessons videoed - we have an idealised perception of what we are like in the classroom and how we come across. Seeing yourself actually teach, whilst difficult, is almost always a good learning experience. I would add that it is unliekly that you are the best teacher you will ever be at the moment - you will carry on learning and improving for the next few years (I have been teaching for 15 years and each year I do things slightly differently and improve on my practice from the year before). Don't allow yourself to fall into the trap where you think you know how to do it all. Ask for advice, ask to see colleagues teach and ask your HoD to come and observe you to get feedback.