After a long bout with Kidney failure, my beloved Kat died just after his 7th birthday. I knew I would be upset, but was surprised at just how upset I was. I went to my coworkers and professors (I was in school at the time) and explained the circumstances and why I would not be operating at full capacity for the foreseeable future.

I was astonished and deeply touched by the depth of understanding and support I recieved from my peers.

I was able to work through it in part by riding my bike. But if you have a long commute in heavy traffic, this might be unadvisable. However, I suspect you'll know when the time is right.

As somebody else pointed out, time is the only thing. So take whatever you need. Loosing a pet is every bit as stressfull as loosing a close relative. Perhaps more so, as there is not always the support network you would get for a human. So, if you think of this more in terms of loosing a close friend or relative, it might, perhaps, be easier to manage and reconsile your grief. And also, know that it's really okay.