Do I have Cystitus? Again?

I was lying in bed this morning, and I felt like I needed a wee, but it felt diffrent, and I thought in my head oh great I hope i dont have cystitus? Turns out I think I do. Its really painfull this time though. Usually when I have it, i go for a wee, it hurts, then the poin goes, but this time im in pain all the time, before and after i wee(but hardly anything comes out). Please help? what is it?