She added: "I didn't blame him for it, I just was angry that it happened on his watch. Because, while accidents happen, never have my children been injured on my watch."
Tameka feared the worst when Usher called her about the accident as her 11-year-old son Kyle, from a previous relationship, died following a Jet Ski crash last year.
She said: "I was at a dental appointment and he doesn't call me regularly, so when I saw his number come up I immediately jumped up. I figured he had the boys. I need to get this.
"It was like I relived it (Kyle's accident). My brain went into all those modes. I even said on the phone, 'I've had this call before.'"
Usher's aunt, Rena, was looking after the two boys when the accident occurred.
Tameka was granted a request for an emergency custody hearing, just one day after the accident, but a judge denied her bid to regain temporary guardianship of the boys last week.
The 42-year-old intends to appeal the judgement, as she wants more access to her kids.
She said: "I'd like to have my first right of refusal, which means when he is not present, the kids come home to their mom.
"They don't stay home with the nanny and watch whatever show he's on. They come home to their mother."
Usher V was released from hospital earlier this week and is said to be doing well.
- Bang! Showbiz