Sara, The first rule about being a bike racer is feeling good about your results. I have several DFL to my credit as well as a few wins and everything in between. And I suspect that will continue. And we all start at the bottom of the peloton and work out way up. So you need to feel good about your results. Consider this...you have results and most do not. It takes courage, motivation, perseverance, training, skill, tactics and some luck to do well at bike racing. You have the first three components.
Results are always a function of who shows up for the event. I raced team pursuit last year at elite track nationals and came in DFL. Well, I was competing against the best in the USA and our time was not horrible. It just was not good enough. I like to race, I like to train, I like team pursuit, I liked my teammates, I learned a lot, I had a lot of fun, I improved my fitness and skills. What is not to like? We all wish the results were better and sometimes they will be.
I am getting older too. My reason for being here is to give you other guys hope. Yes, one can improve as we age both in strength and power. You are getting older but so what. HTFU and get on with the work. I never focus on age other than when I select my age group for state and nationals. If one focuses on age and that younger is better it will drive you crazy. It is counterproductive and nothing we can do about it and you will deprive yourself of some of the most fun and great relationships that racing has to offer.
I completely agree with A'Jet. You never know how other people feel when you are riding. Part of learning this sport is knowing what is really hard and how different situations affect all racers. You may be hurting and suffering and so is everyone else. They are good at not showing it. You crack and think you suck. The reality is you need just a little more mental toughness to hang in until the other guy cracks. That skill takes time to develop. You probably have much more capability than your brain lets you tap.
Also, over time you will get to know the racers you compete against. You will measure yourself against them. i suggest you do some time trials and hill climbs to get a sense where you stack up against other women. These races will also build your power, endurance and mental toughness.