I can completely empathise with you, I work two jobs, both in shops and one serving food. On average of 35-40 hours a week. I'm 24 and get spoken to like a child and feel invisible half the time and take any comments or critisism to heart, which then puts a heavy feeling on my chest and I've had a bit of hair loss from it too! I think it would be a good idea if you have someone you can rant to, either a friend or someone online (just not mentioning your work colleagues names or the place of work) and to also sit down and have a think about it. Think about how well you're doing in certain parts and ask for advice on anything else, try and remember that at the end of the day, you get to go home and relax and that, more importantly - people see you differently to how you see yourself. So, you may have been made to feel like crap, but you're not that person anymore and that's a persons opinion, it doesn't make it true! :) stay strong and be honest with yourself and rant away x