Couple of things.
Don't worry about a lumbar wet tap. A headache isn't the worst thing in the world and it rarely is dangerous.
Second thing - use better control.
Thirdly, think about the anatomy a little bit. I suggest moving up a level from where you think you are at. Look at this MRI T1 Sagital (fat is bright) I pulled off the internet - but this is very typically of everyone. The bright signal next to the arrow is the epidural fat. The black lines on each side are the ligament (posterior) and the dura (anterior). The epidural space at L5/S1 is very thin, and in most, not even visible on MRI. The epidural space increases as you move up and is often the widest at L3/4, maybe L2/3. However, notice that the space in a single level varies dramatically to almost non-existent to very wide (3-5mm). The widest epidural space is in the middle of the space (in a caudal-cephelad direction), so try and do your best to be in the middle of the space.
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