The hematoma may have burst from a secondary infection. The white substance is most likely purulence from the infection. The wound should be assessed by a physician to determine if an antibiotic is needed, or if the wound should be debrided.
You may not be allergic. The medicine may be drying out your skin, and your skin might be reacting to this by making more oil. Make sure you are using...
When a hematoma has inflammation, and swelling as you describe, it raises the concern that it has become infected. This needs to be examined by a physician to be determined...
The safest is what the video recommends. The basic rule of thumb is that you know when you're getting close to the blood supply or the quick when you see...
