New dull blades

I'm still fairly new to this, maybe 6 months or so of using a brush & safety razor full time. I have used a safety razor off & on for a couple of years, but with canned goo. I have always used the same blades, got them at the local mart, I don't know their name because it isn't on the box the are in. The last time I bought, they had changed blades and carried Wilkinson, so that's what I have been using. A week - 10 days ago I changed blades, took the Wilky out and put in one of the others. WORST SHAVE EVER. Three days in a row. Put in a Wilky, got DFS/BBS shaves. Changed blades this morning, used the last of the other blades. WORST SHAVE POSSIBLE. Razor burn, have stubble, face is raw. I'm glad it was the last blade, it has been disposed of properly.

Now the question. Did these blades dull in the case, or did I just adapt to the better/different Wilky blades? I don't recall having this problem with them before now.

Has anyone else had this happen?

Johnnie

They came pre-dulled from the factory.

Only half joking there. Different blades are different, and cheap blades are generally worth what you paid for them... "drug store" blades can be very hit and miss (even if you paid $5 for a 5-pack).
Derby blades and the R41 do not get along with my face. Bloody mess.
Astra SP is much better, and Gillette 7:00 Yellow is a buttery smooth dream.

Just an example of how different faces react to different blades.