Starter doubling and then goes inactive - feed or no?

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I tried making starter a year ago and gave up because it never rose. I finally decided to attempt another a few days ago and much to my surprise, 2 days in, my rye starter looked gorgeous just 7 hrs after feeding 1:1:1 (73 degrees inside)! I was so excited. Well...

Day 2 1:1:1

I didn't realize I was supposed to feed it right as it began to fall. I thought I was supposed to feed it every 24 hrs. The next morning it had completely fallen but it was the 24 hr mark so I fed it 1:1:1 (71-72 degrees inside). No rise at all. This morning I fed it again. I figured maybe my starter was hungry and I underfed it the day before so I left less starter behind and used an extra 10g of flour and 10g of water but not so much as a bubble yet (9 hrs later ~70-71 degrees indoors). 

Do I feed it tomorrow even if there's no sign of activity? What did I do wrong!!! I was so excited.

That's classic infant starter behavior: an initial burst of activity driven by bacteria followed by a quiet phase with no visible activity.  It's kind of like a duck; all calm on the exterior but lots going on below the surface.  

Wait for it to make some more bubbles before you feed it again.  Stir it once or twice a day, if you want to.  

After the next feeding, let the starter expand until it stops growing.  Once it begins to collapse, remove half and feed again.  Maintain that pattern for a few days and you should have a bouncing starter that is ready to raise some dough. 
Paul