Did you talk to a doctor? Maybe he can prescribe you something. Its probably a chemical imbalance or something triggered it. For now I recommend meditating. Meditating is not easy at first especially if your you have so much anxiety. But you have to fight it. There is a bunch of ways to meditate. Could be threw music sitting in a hot tub whatever. I personally do not recommend music because mediation is about clearing your mind. So to do so is.
1. Take off your shoes cross your legs put your arms to your side and relax them.
2. Close your eyes and clear your mind from every thing. Which ever thoughts pop up push it away.
Do it for about 20 min a day night or day before you get out of bed or before you sleep.
Good Luck