BTCUSD is currently locked above 4,500. If it continues to keep pushing up, it could rise parabolically and the most fearful thing could happen - a huge correction.
For now, I see BTC touching 4,800 before going down. It could also push further upwards if the market demands so.
These are the support I see in order of critical level:
4000 - a bit critical
3500 - average critical
2500 - most critical