Anything to worry about?

So I’m about 5 weeks pregnant and lately I absolutely do not have an appetite. I’ve always been skinny and didn’t really eat more than once a day but being pregnant I feel bad for not feeding myself more, and my fiancé is getting frustrated because of it also he says he doesn’t want me not giving our baby what it needs, and it makes me feel bad. I know he’s just looking out but from what I understand first trimester it’s normal to experience this and normal to even lose weight sometimes. Is this true and did anyone else experience this? Should I be worried?

SN ( I don’t have an eating disorder because I’ve been asked just fyi )