Oh Well done! First ones always the hardest, but it gets easier! I remember my first time, over a year ago now...I made the same mistakes as you, Slow down, then slow down some more, let the jokes breath, give the audience time to process your material, allow space for laughs! Stand ups a feedback loop with the audience, not a recital so concentrate on just being likeable in the early stages. I started a year ago at 60, won a regional Comedy Quest heat, and got in the nationality grand finals down to 12 from over 200+ new comics here in New Zealand. I've performed a total of 18 times so far, won the heat on my 8th, finals on my 14th gig ...it definitely gets easier as you tighten your material and get some stage time up. If ya have a particular bit that always gets laughs - expand it, add tags and secondary punchlines, it's economical and saves introducing a new set up. Keep doing it, keep it light, have fun and enjoy the journey!