Psychological resistance is a real thing in the market and I think your chart shows it. Big numbers often take a few runs to overcome. I am not surprised at the pullback. I thought it would overshoot a bit before retracing but the 5000 level was just too strong.

I look for consolidation for a while before BTC moving past 5000 and making a run at 6000. We might get a larger pullback at the 6000 level depending upon how fast the run up is.