Should i pop a water blister from bed bug?

No - that can ^ risk: Of infection & scarring. Blistering usually is due to an allergic rxn. See dr. Bed bug bites may cause no sx's/signs in some except for 2 small points where skin was punctured by bedbug. When there's a reaction, it may show from an hour to several days after bite. It can cause itchy, pink, swollen, lesions w clear center. In cases of hypersensitivity blisters may develop. A telltale sign is line.