Since I couldn't finish the stuff for my other milestone because the middle tier is broken, I went ahead and skipped to the work for the last milestone for this feature. The dev lead on the team that originally owned the feature had estimated 2 days. I had bumped the estimate up to 3 days because my group (i.e., me) was unfamiliar with this part of the code base. The previous milestone (the one I am waiting on other people for) was originally estimated at 3 days. I bumped it to 5 for the unfamiliarity factor. It took me about 9 days. Some of that time was context-switching though. That's time I lose because I have to go do other things. For example, I have to drop the work and go fix a live site bug where $1,500 items are being sold for $1 (true example, and the problem was hard to diagnose but easy to fix). I spend 3 days working on that. Now I have to switch back to my real work. But it takes me a half a day to get back to where I left off, for various reasons. My schedule gets bumped 3 days. But the estimate for this feature now is a half day longer and the end time is now a half day further out.
Now, my rule is that I always assume that if the early part of the work goes longer than estimated, that later work will also go longer than estimated. So I re-estimate that this second feature will go at about the same percent over. So the estimate for 3 days is now 5 days.
However, for once the gods were looking on me with favor! When I looked at the existing code in depth, I figured out I could extend that code, rather than write a bunch of new code to handle the new feature. Feature written and partially unit tested in about an hour. Won't be able to completely unit test until after the middle tier stuff is fixed. Basically, all I have to do now is some tweaking and set up some stuff so the international team can translate the text.
Stress level down, although caffeine level is still way high (shouldn't drink caffeine to deal with stress and lack of sleep, it's really bad for me). Should be able to sleep tonight and eat tomorrow.