Shaker Aamer, the British-based former Guantánamo Bay detainee finally freed this week after nearly 14 years in captivity, was so mistrustful of his US captors that he did not eat anything on the plane flying him home for fear it might have been spiked, one of his doctors has said.David Nicholl, a consultant neurologist who has campaigned over the plight of detainees at the US base and who is part of Aamer’s post-release medical team, said the 46-year-old was currently undergoing tests to determine the state of his health.Aamer was suffering from severe headaches, sciatica and other back pain, Nicholl, the first doctor to see him on his return on Friday, told the Mail on Sunday.Nicholl told the paper that Aamer had “very serious problems trusting doctors after what happened to him”. During his 14 years at the detention centre, Aamer had his blood forcibly taken and was force-fed when he went on hunger strike.Among the tests being carried out were toxicological tests to confirm Aamer had not been poisoned, Nicholl said. Facebook Twitter Pinterest Detainee 239: who is Shaker Aamer? Aamer “did not eat or drink anything after boarding the plane at Guantánamo. He was still fearful that they might spike it with something, even at this very late stage,” the doctor said.He added that the former detainee recognised that “the psychological impact of what he’s been through is going to be at least as big as the physical one. He really has been to hell and back”.Trauma experts and former hostages have stressed that the psychological toll of the long incarceration could take much longer to get over than his physical ill-effects. Former hostage Terry Waite has urged Aamer to “withdraw for a while” from public view to concentrate on his recovery.Nicholl told the Mail that Aamer’s changed appearance might help him do this: “He looks a lot older than he does in the familiar pictures. That might just be helpful, because it means it’s going to be easier to do what he most needs – to live quietly with his family beneath the publicity radar.”He added that when Aamer returned to the UK he brought with him a single red holdall bag, tagged not with his name but “Prisoner 239”, how he was referred to in Guantánamo. Nicholl said: “So far as the Americans were concerned, that’s who he was, right to the end.”In a tweet on Sunday morning, Nicholl said he would not be discussing Aamer’s health any further due to confidentiality issues.