Can enemy give nightmares? Is there anything to do to protect and stop nightmares?
I dreamt all night islam was truth and woke up with bruises on legs..
Fuck islam...
I have theory that its just bad energy leaving me as I am unblocking my chakras right now.

Yes, enemy entities can and will cause nightmares to those who lack protection. Putting in more work towards your AoP should solve this issue. Make sure you do the Returning Curses I & II atleast twice daily, as well as to participate in the RTRs to gain more protection from the Gods.
https://www.satanisgod.org/www.angelfire.com/empire/serpentis666/Returning_Curses.html
https://www.satanisgod.org/www.angelfire.com/empire/serpentis666/Returning_Curses2.html

clean your aura and chakras, Visudhi. Do aura protections many times daily as possible, add Algiz rune to your meditations daily it will help. I had the same problem before.