A mum-of-four died of a blood clot after thinking her breathlessness was a symptom of anxiety.
Suzanne Stoakes was found by two of her children in the morning of May 7 not breathing.
Kieran, 22, and Carys, 19, performed CPR on their mother at their Port Talbot home, but their efforts and those of paramedics were in vain, Wales Online reported.
Oldest son Ashlee Roberts, 28, said the 50-year-old's death has left a "huge hole" in their family as well as within the local community.
"On Friday night, May 7 she rang me and said she wasn't feeling too good and that she was finding it difficult to catch her breath and said she was feeling anxious," Ashlee said.
"She wasn't in pain and sounded like she was breathing fine. She went to bed that night and then in the morning, my younger sister called and said she needed me to come down and look at mam because she wasn't well.
"She was laying in bed and again said she was struggling to catch her breath.
"We called NHS direct and she spoke to a doctor on the phone for a while and he said that it might be anxiety and that they would put her on medication to help with that.
"She wasn't in pain and had no other difficulties."
Ashlee said his mum then started to get tired d told him she wanted a few hours to catch up on lost sleep from the night before.
"She said she would phone me later to let me know how she was," he said.
"I went home and then about half-an-hour later my sister rang to say she had stopped breathing and that an ambulance was on its way and that I needed to go back.
"I got there within 10 minutes and the paramedics were there doing what they could. They told me my brother (Kieran) had been doing CPR himself and that it was something to be very proud of.
"Then they announced (that she had died) and they weren't sure what had caused it.
"They did a post-mortem and found that she had deep vein thrombosis which caused a blood clot in her lung some time over that night."
Ashlee said it came as a "total shock" to him and his three siblings because Suzanne was healthy and active.
He said the sudden nature of her death had made it particularity painful.
"It would have been her 51st birthday on June 6," Ashlee continued.
"She was was physically fit, she had never driven in her life so she always walked everywhere and kept active.
"She lived near the beach so she often would walk the length of the beach every couple of days and sometimes would ride her bike, so it really was a shock."
He described his mother, who was a carer at Alma Lodge care home in Taibach, as being "fun-loving, creative, but most of all very, very caring".
He said: "She's always loved caring for other people and always put people before herself.
"She would take residents she cared for to the hospitals when they needed treatments and would sit with them. She was selfless.
"She'd walk an hour to work every day and do 13-hour shifts, then stay on late overnight because she wouldn't leave them there unless she knew they were comfortable.
"A lot of people in the community knew her because of the care work she did.
"Families and friends of the residents would always say to us 'we met your mum last week, she's looking after our dad and she's such a lovely person'.
"She was really fun and very much the life and soul of the party. She had a lot of close friends through her job - one of her best friends, Zara, she met in work and she was about half her age - she was always so young at heart.
"The four of us had a really special sort of bond with our mum. She was our best friend and she would always be involved if us four got together as siblings."
Ashlee said Kieran and Carys are staying with him for the time being, but they are currently raising money to try and help them move back into the house they shared with their mother.
Suzanne rented her home and was in the middle of landscaping the garden and making some interior improvements at the time of her death.
The family, with the landlord's blessing, hope they can continue this and turn it into the house Suzanne always dreamed of.
Money raised would also go towards Suzanne's funeral costs.