a) 35 is not old
b) As you age (Shock, horror that awful word on MN - you'll be an old woman) if you're catrrying a bit of weight, you won't look so haggard as thinner women can sometimes look
But
c) try doing something interesting, satisfying, valuable, absorbing, difficult, selfless in your life so that your "looks" are neither here nor there. You sound far too invested in thinking that our "looks" determine your value. I find your OP really upsetting and sad that you as a full rich human being with imagination & life & talent, should limit the way you think about yourself.
That society has conditioned you to value yourself by your looks makes me angry with society, and sad for all the valuable energy that women waste in trying to be "beautiful".
Ageing is inevitable.
The alternative is worse (think about it).
The best way to deal with this is to value yourself for your character, your achievements, your relationships, your talents, your caring for others.
And for YOU yourself. Just that is enough.