Hello dude, my 2cents ..
it seems a nice idea to make your own medicine, but be aware of what you do while mixing all this. Making a such mixture, for me, disgust me. I can't help you with the interaction from all this component between them, please be aware of that.
Your cream, if finished, may contains much more chemical than organic compound.
If your way is to make organic, please stay with safe & effective organics compounds.
We may not want to buy cream with tons of chemical, but what about making your own with tons of chemicals ? Should it be better to make our own cream with, more or less controlled dosage of potential harmful substance ?
Please rethink what you do, and it may be better to have more actions specific cream than a all in one cream. We all know that the medicine than cure everything seems to not exist, atm.
Thats why there is plenty of choice in medicine, with different and complementary action.
Did you looked around Peganum harmala for pain ?