How many threads? Try 3.
No, your math is probably right, and 250 H/s is probably high for a laptop. Maybe a better word than mining (which suggest perhaps a steady stream of useful minerals) to describe the process is prospecting or wildcatting.
WAY high - my MacBook Pro has a 3.0ghz dual-core i7 Haswell processor, and that does 34h/s:)
Something is messed up there, maybe extreme power management, using the wrong number of threads, no-AESNI build, etc.. You should get about 60 H/sec per thread.