Is my body just saying, that's it, no more?

Some great advice already, so won't repeat. But I just wanted to add.

You stated:
I admit I am not the most precise calorie counter, I guesstimate here and there if its not something I can just scan. [/quote]

Along with more precise weighing & logging, to track more accurately. Make sure that when you scan items, directly into mfp, the calories/nutrition info that gets logged, matches what is on the packet.

As these data base entries are still user listed and may have/often have been entered wrong.

I know someone who had been tracking that way. Mainly eating food that could be scanned, as a convenience & accuracy.

But hadn't realised data was wrong and was therefore eating more calories than realised. (Affecting her loss).

A scanned ready meal Tesco lasagne, may be 610 cals. By scanning barcode, Tesco lasagne 400g came up & was logged. But data, not checked. It was only logging as 400 calories.

210 calories underlogged for 1 meal, without realising. The smaller the deficit, the more it affects end results.

Also (if you want/need) greater accuracy, you still need to weigh items that can be scanned. As a 400g premade lasagne won't necessarily weigh that. With higher calorie foods per weight, the more inaccurate logging.