bed bug is hard to remove. check a report by NY housing board (google it).
The most effective stuff are: stefarb (see report), and another chemical. Stefarb has 70% alchol + other chemicial. Current bug killers sold at Lowes or Home depot are not effective enough due to bedbugs developing ways to live even you spray them.
Your best bet will be likely to get a pest control company (cost about $200 ), $30-40 per visit after that.
You can also order stefarb and DE on Amazon.