Hi, I was wondering if it was common to go into SP when you wake from a lucid dream. I have a fear of SP and would like to know this before I attempt to LD. xP
Yes, it is possible in some circumstances, however SP is nothing to be afraid of. It’s a natural function that your body does every night. Sometimes people are afraid of the HH that they might get, such as images of an Old Hag. However, you can control these images just like an LD. It’s based on what you expect to see.
However, if the concept still frightens you, here is an article describing the best ways to get out of SP
I have had SP coming out of a dream, but if it’s a REM dream and/or a lucid, usually I don’t see anything. It’s often a great way to go right back in the dream. Don’t be afraid of it, and if something does happen, remember that it’s not real. I often don’t get much HH myself, but it’s different for everyone. Doesn’t necessarily mean it’s going to be bad for you though. 
It may happen, but chances are that it wont. And IF you do, it is nothing to worry about just be thankful that it is there. After some time i have actually come to enjoy SP it is just a neat unique feeling and goes away soon and there are many ways to exit SP but do not be affraid of anything about lucid dreaming it is almost ALL fun.
After a dream, I find myself in SP usually in 1 of 10 cases. I immedeately recognise it and use the SP to get into a LD.
After you’ve experienced SP for a few times, you’ll have nothing to fear about. OFC, it was scary for me too the first few times I’ve experienced it.
If you want to have a Sleep Paralysis try, first, to use the WILD Technique (Wake Induced Lucid Dreaming). And it is natural to have fear of this, but with some practise, you will overcome this “Protection”!