urgent-- fever advice needed

[Lernermichelle]

I got home and Lucy felt warm. I took her temp about 20 minutes ago and it  
was 105.7.  I gave her doxicycline (she has been on amoxi) and fluids (150  ml) 
and put some ice under her paws. I took her temp again and it was  105.6.  I 
am trying to figure out whether to take her to the ER or  not.  At what point 
do fevers get dangerous? Should I take her? 
 
Thanks,
Michelle