will tanning in a tanning bed kill my little swimmers? or in anyway keep me from having kids?

Answer 1

No, but you won't live to see them grow up if you have any as you would have died from melanoma skin cancer.
Seriously, why would you want to increase your risk for cancer for cosmetic purposes? If you must have color, consider professionally applied spray tans. They look very good and have no lasting damage to your skin or sperm's DNA. (Unlike the UV rays in a tanning bed)