I never used numbing cream. The tattoo shops I've been to charge like $20 for numbing cream application.
Pain is subjective, but you mightttt get addicted to the pain
The adrenaline rush from getting inked is something else. From my experience, the most pain was when the tattoo machine is at a boney area. My ankles were my quickest, but most painful tattoos I had. And it hurts too when the coloring/shading occurs for a long period of time, since the skin gets super tender after awhile. What are you planning on getting?
Aftercare -- I used regular antibacterial soap. Just lathered the soap in my hands and rubbed the fresh ink. Then I used a thin layer of aquaphor when the area is still oozing/tender, for like the first few days. Then I switched over to the regular eucerin lotion i use.