I definitely know what you feel like. I'm in a very similar position. ~4 years at my previous company where I worked my way into a Developer position, and then

I definitely know what you feel like. I'm in a very similar position. ~4 years at my previous company where I worked my way into a Developer position, and then recently left to work with a friend in another company. I like the company I'm at now and although it's full-time with no end of employment in sight, I know eventually I'll have to go through the normal process. I've worked at 2 companies now as a developer at varying positions of development, and I don't feel qualified to pass a single interview. Luckily I have time to prepare, but I really need to get that established. Probably take the time to do a proper CS course to boot. Keep your head up, and thanks your reply :)