It’s a right of passage, I switched all my hotends to fixed blocks, accidentally loosened the block once on the older style hotend after torquing correctly and enveloped the thing in petg, it kinda vitrified too or something in the heat, was like glass so no getting that off.

Generally, blobs off of your hotend, estop it and take a look, that’s a huge tell for a leak.

Worth keeping a few spares around, at least for stuff like nozzles, blocks, heaters and probes.