Nap time troubles

DS moved to 1 nap per day a couple months ago.  He dropped his afternoon nap, but continued with his morning nap which is around 10:30/11 for 1.5-2 hours.  Over the past week he has been putting up quite a fight when I put him down for that nap.  I like to wait until I see him rubbing his eyes or something like that to do our naptime routine (consisting of bottle, lullaby, white noise, and cuddling).  He is pitching a huge fit and kicking about during our cuddling time.  Yesterday I just gave up and went to put him down at 1:30 when he looked very tired.  He still fought it and even cried hysterically before he passed out for 2.5 hours.  He is obviously tired for these naps because early in the routine he yawns and closes his eyes, but then he fights it.  He starts talking to keep himself away.  What the heck is changing? I can't have him go without a nap because he becomes overly tired and absolutely wild - he gets really uncoordinated too and tends to hurt himself by falling, etc.  I should also say, it takes about 45 minutes to get him to fall asleep now for the naps.  The only time it was shorter was last Saturday when he skipped his nap and then just passed out after his 3:30 bottle.

So my questions: Do you think he wants to push the nap out to later in the day?  Could he just be going through a phase? Or, is this normal? 

TYIA for you help!