I did the same thing- did 4 days of 5mg, then a few weeks of 10mg.
At the very beginning, I had SLIGHTLY increased anxiety. There was one morning where I woke up in a panic attack, but an ativan quickly cut that out. Each time I increased the dose, I would have slight problems sleeping for 1-2 nights but nothing major.
Even with that happening, Lexapro has CHANGED MY LIFE. I started 15mg last week, and around the same time noticed a complete turnaround. I used to take ativan daily, now need it 1-2 times a week. My anxiety has diminished almost COMPLETELY. I feel normal, balanced and sane almost 24/7. And even the rare occasion where I get a little anxious is hardly that bad at all. I used to have a panic attack just about every morning. Now I haven't had one in over a week, and every day gets even better.
Lexapro is known for very low side effects. I HIGHLY recommend going through with it. It may take over a month to kick in, but it works very well.