I m a hypochondriac person.i have health anxiety.my question is.if testes shrink and raise due to repeated episodes of fight and flight response due to stress.does it makes testes to be warm or lead to watery or low semen??

Yes you are. And no, these issues make no difference in your health or fertility. You need professional counseling. Good luck.

Retractile testes is a normal circumstance. Quit worrying about it. For healthy diet: http://www.choosemyplate.gov/., exercise 30 minutes/day, drink enough water daily so your urine is mostly colorless, have safe sex, no tobacco alcohol weed or street drugs. Get HPV, Flu and Covid vaccines. Wish you good health!