"What else can it be?"

BB

I haven't had a period at all this month. Had two tests both came back negative and between a passing comment last night and a discussion this morning I'm beginning to think my partner is just going with "must be pregnant" last night he mentioned how I could be like my sister (sisters first pregnancy she had to find out by blood tests and even when she KNEW she was pregnant tests were still saying negative). Today I said about how we still don't know and he went "they've done blood tests, scans, and internal exam what else could it be? There's nothing wrong or they'd have found it" I said how my doctor wants more external exams but I'm starting to doubt it myself. But I also know doctors mentioned my weight which bothered my partner a lot so I think he's refusing to think that could be a part of it and I'm worried he's just trying to write off any concerns because he wants it and he's going to get disappointed if it turns out I'm just freakishly late. I guess my question is do you think he could be right and this must be it? Or could he be trying to reassure himself that it's nothing because of the fact that doctors haven't found anything so far? Do I dare to hope or am I just repeating myself like other times we thought it must be