Hi...Thanks for your query. Can you tell me, whether your husband is able to achieve adequate erection for a successful vaginal penetration? How long does it usually takes before he ejaculates? Is he currently on any medications? Do you both as couple engage in foreplay before actual intercourse & what form? Based on information you provided, I can conclude that, due to some yet untold problem or just by chance, your husband might have had 1-2 instances of erectile failure or premature ejaculation prior to reaching climax/orgasm. These instances are fairly normal, are common & can happen with any couple. But because of his status of a testicular cancer survivor; these instances might have caused stress/pressure on him with subsequent assumption of spectator role where rather than enjoying sex; he is unconsciously more preoccupied with how he is performing etc. & hence getting these symptoms. You (both as couple) should get yourself evaluated by a Urologist followed by a Psychiatrist for management of this issue. Good Luck