That's tough to take, but probably bad luck. What are your node stats? I have nothing close to your HR, but I have gone two days @ 1.1 TH/s without a share recently. Bad luck and then from the 16th to 17th did 8-9 days of mining on P2pool. The best day. It made up for it all.
You running on windows on linux?
Got any screen output? Any P2Pool errors?
I have been having some Bitcoind crashing issues lately. I'm trying to work on those now. Pretty sure it's memory related. I hope.
Mining for 13 hours at 5.2TH/s, expected time to share 2.0hrs....
Actual share obtained so far: 1 total (1 ophaned, 0 good) ......
Pure bad luck or setup issue???

Seriously, should have got 6 shares under the "expected" scenario.
P2Pool BTC
Graphs
Version: 13.4
Pool rate: 2.00PH/s (12% DOA+orphan) Share difficulty: 8820000
Node uptime: 13.5 hours Peers: 6 out, 0 in
Local rate: 5.31TH/s (1.2% DOA) Expected time to share: 2.0 hours
Shares: 1 total (1 orphaned, 0 dead) Efficiency: 0.000%
Payout if a block were found NOW: 0.00823785 BTC to xxxxxxxxxxxxxxxxxxxx. Expected after mining for 24 hours: 0.0665 BTC per block.
Current block value: 25.05109951 BTC Expected time to block: 14.2 hours
