Yes, it is definitely starting to show a low light habit. It is not showing full on light starvation but definitely you can see that the body is stretching and the spines are starting to 'weaken', especially the central spines are less prominent.
More light, if possible, but unless the plant goes in full on stretch mode it could be OK for a while longer in these conditions... but if it goes super stretchy it is going to be irreversible so do not wait too long to give it better light.
