Mitesh Patel, 37, also blamed his panic when he was asked why he did not attempt to resuscitate 34-year-old Jessica Patel when he found her unresponsive in their home in The Avenue, Linthorpe, Middlesbrough, in May. Jessica grew up in Leeds.
Teesside Crown Court has heard Patel, who was repeatedly unfaithful to his wife with men he met on dating apps, denies murdering her with the aim of starting a new life in Australia with his soulmate, Dr Amit Patel, and cashing in a £2 million life insurance policy.
The defendant first told police and his family he had last seen his wife around midday when he left the pharmacy they both ran.
He now says he had seen her for 42 minutes at their home after 7.02pm when she had finished work, and they spent time chatting together before he went out.
Nicholas Campbell QC, prosecuting, called that "the big lie", and asked why Patel had not told the truth about those "precious" last minutes with his wife when the first officers arrived at the scene.
Patel replied: "I panicked.
"Jess was in that state and I was the last person in the house.
"All that came to mind is, 'the police are going to think that I have done this'.
"Having read things in the press and seen things on TV, I panicked and thought: 'Crap, I'm going to get in trouble for something I haven't done here.'"
He said the first time he told the truth about his movements that night was some weeks later to his legal team when he was being held in Durham Prison.
After Mr Campbell asked about Patel coming home to find his "stricken" wife, the defendant claimed she was unconscious, and he could not tell if she was still breathing so he put her in the recovery position.
He rang 999 and asked for the police.
Mr Campbell asked: "If she was alive, why didn't you ask for the ambulance?"
Patel said: "The point was I was already panicked and scared, I didn't know what I was doing."
Mr Campbell asked: "Is it because you knew before you got back to the house that she was long dead?"
Patel denied it, saying: "No that's not true."
Mr Campbell asked him why he had not tried to perform CPR (cardio pulmonary resuscitation), and Patel said he did not know what he was doing at the time.
When the prosecutor said Patel was taught some CPR when he did his professional training, he replied: "I'm not a doctor, I'm a pharmacist, I deal with medicines."
Mr Campbell suggested Patel already knew he had "lost" his wife, adding: "You were not going to waste your time to revive the dead."
The defendant replied: "That's not true."
When Mr Campbell told the defendant he was going to ask questions about him being unfaithful, Patel replied that they had already been through that.
He said: "I have my parents and my wife's parents in the gallery.
"Please can you be a bit more sensitive?
"I'm getting very tired, I have been up since 5am."
The case was then adjourned for lunch.