I'll join you in raising a glass to the first sketchbook completed - and drink to the second one being started. You've done well indeed, and pushing yourself that little bit further each time you sketch has paid off, some of these last ones are delightful in the tone work and show increased familiarity with the subjects and your art materials. Now, onto the second sketchbook, and a little tip, as soon as you buy it, scribble all over the first page, doodle, draw stick figures, whatever, just ruin the first page. I always find a new sketchbook terrifying, I want it to be the best thing ever from the first page, and so you end up waiting forever to start it, just looking for that perfect sketch to come along.