Periodontist appears to be too aggressive when probing by "poking". can the probe push further down past the underside of the pocket in some cases?

Possible: The periodontist probably was trying to get an accurate reading using the prpbe because the depth of the gum pocket can determine the type of treatment required. Hope your gum issues resolve quickly.

Technically yes..: .. But highly unlikely. The perio probe is not a sharp needle, but rather a blunt end instrument. The procedure may have been painful since your gums are inflamed. If it was pushed through the attachment into your soft tissue there would have been a lot of bleeding.

Perio probing: There are vast differences in how it feels to have perio probing done, and it depends on the patient as well as whether a pocket is more or less inflamed. There is, however, a reasonable amount of force which needs to be applied, beyond which is unnecessary. Unless it is a new surgical site, or an implant prosthesis, too much force would not damage it permanently, but it's unnecessary.

Probing: When there is inflamed gum lining the pocket, it can be sensitive to probing. Minimal force is needed. Too much force causes the probe to go past the bottom of the pocket into the tissue. I urge you to share your concerns with your periodontist

Probing: Probing required to document the depth of the pockets around your teeth. Periodontist would have to exert extreme force to push the instrument through your tissues. I know probing is uncomfortable, but it is necessary, especially if you have active gum disease.