Am i being silly

I don't know if I sound silly or not But my fiancé and I have recently started trying and I feel silly for saying this but I'm actually embarrassed that if I get pregannt and go to the doctor he's going to tell me I'm over weight in front of my boyfriend and I'm scared of that. I'm 5'7 and 165 pounds. I don't look fat or anything bc of my height it spreads out evenly but I know my finance thinks I weigh  less then I do. Iv actually been losing weight I weighed 178 last month but started counting my calories and now down to 165 my bmi for my height is 159 pounds im pretty sure I can lose the last 6 pounds before I get pregnant btw I'm 18, am I being silly ? My finance loves me and always tells me he loves my body so it's not him making me feel this way I'm just nervous. I know he wouldn't think anything of it iv just been really self concerned about my weight since high school in 11th grade I was a striking 196 pounds now down it 165. Any other women feel this way ?
The first pic is me in high school and second is me now.