Most people don't have a burning desire to do a thing. Most people fall into stuff, find something they didn't realise they'd like, then that leads to something they didn't realise they'd like even more...

Happened to me. I went into Computer Science because I didn't know what else to do. Then, I wasn't passionate about anything, but I was leaning toward IT. But I got offered an internship as a software developer. Now I'm a software engineer, and I love programming.

Just keep doing what you're doing. Graduate, get a job you don't hate, doing something that uses your skills. Wait a couple years, see how you feel. If you start hating it, find something else. Do you hate your major? Then switch. If not, stick it out. At some point you'll either realise you like your job, or at least don't mind it; or that you hate it; or that you know exactly what you really want to be doing.

I don't think anyone really has an epiphany and knows instantly what they want to do, or grows up knowing. Life just kind of happens when you're not looking.