I quit my job with a baby on the way, 20 months ago. In that time, the economy has tanked, so even if I wanted to go back to work, I wouldn't be able to find one anywhere near my old salary.
Am I sorry? No. I'm still very, very happy I had the guts to take the plunge and do it. The fear of not having a steady paycheck is much worse than the reality. Now that I know that, even if I do get another job, it won't have the same psychological hold over me.
However...
I had worked a lot longer than you have, before I made that plunge. While I wish I had done it earlier, I think that 2.5 years is too early. At 2.5 years into your career, you're still an apprentice. You have a lot that corporate life can still teach you.
Here's what I did.
Every time I felt like you feel, I found another job. I found it before I quit my first job, the safe way. After about 2.5 years, almost like clockwork, I'd feel restless, and cranky with my current status, and go find another job. I learned a lot that way and made a lot of friends.
When you think the time is near for you to take the plunge, do what I did. Say to yourself, "this job that I'm starting today will be my last job. I will not allow myself to quit it to find another job. No matter how much I hate it, I will not trade it for a new job. I will only quit when I'm ready not to have a job at all."
That vow kept me in my last job for an extra year or longer. Time I would ordinarily have just hopped to a new job. Finally, I decided my time was now, and I gave my notice, without even having any concrete plans on what kind of business I was going to build. I just knew that I needed to be free.
To summarize, my advice is to job hop for a few years when you get unhappy, just like non-entrepreneurs to. There's a lot to learn that 2.5 years won't teach you.