Rihanna broke down and "wanted to punch someone" after recording her latest album because she was so "overwhelmed".
The 'We Found Love' hitmaker contracted a virus in November and admitted her "crazy" schedule meant she barely had time to rest and recover from her illness.
Asked how hard she worked on latest record 'Talk That Talk', she said: "This is the craziest schedule I've ever been on in my entire life.
"One morning I woke up and started crying so hard. I finally just got to my bed from the IV [drip] and I was just like, 'Good I can actually get to sleep tonight' because we stayed up all night and I finished [the album] at 5pm the day before.
"I get in bed and it must have been two hours in before my phone started going off.
"I was so frustrated I kept ignoring the phone.
"I know I'm sick but I'm the only person who can get it done so it was so frustrating so I was angry. I was so angry, I was so overwhelmed that I was sick, it felt crazy.
"I started crying really, really hard in my pillow. It was aggressive. I don't cry loads. If I cry it's because I'm very angry and I can't do anything about it, because I've run into a dead end. But this time I needed to hear it, I almost wanted to punch somebody."
However, the 24-year-old beauty - who quickly realised no one else could do her job so she
"got up, showered and started to work" - insists the agony was "worth it" because she was so pleased with the finished album.
In a newly-released video interview called 'Road To Talk That Talk' which was recorded earlier this year, she said: "When I got the copies in my hand, it was so worth it. I would never take it back. At times I wished things could have been different and easier but then I didn't really care when I got the album. The fact it was so difficult, the album feels so much better."
Earlier this week, it was reported that Rihanna had been taken to hospital with exhaustion, sparking fears from her loved ones that she is pushing herself too hard.