Hey honey.
There is nothing inherently bad about loosing depth. I let about 3 quarters of an inch go after my surgery. I lost that in the first month or so, partly because I did not put enough pressure on, and then stabalised. but it was ok, I thought what I had was excessive anyway.
But the only way to be sure is to measure it. Get out your ruler if your dialator does not have marks and take note of it. Make that your target, and your benchmark. If it starts to reduce then you need to work harder.
Now at the stage you are at things are starting to really contract, scar tissue is forming. This is where you really need to work it. This is when it starts to get hard. It should not be a comfortable thing to do, keep good firm pressure. I don't know what your surgeon recommended but mine recommended that it should make it very uncomfortable. In practice as a guide you should not start your timing until you reach your max depth.
Something to be aware of is your depth will seem to fluctuate sometimes. Part of it could be that things are no longer as swollen on the outside which makes it seem like you are not going as deep. If your bowel is full that can decrease your depth for that dilation.
If you are worried, dilate more, stick in an extra session a day if you can.
But to be sure contact your surgeon.
It is scary, feeling like you are loosing it, but trust me, if you keep up the dialations then you will be fine. In a couple more months you will be an old hand.
Hugs
