Self Esteem Issues

My first post, I'm sorry to say, is a bit of complaining. This past year has just come at me like a ton of bricks. It started with having to change my major at the drop of a hat at the end of my "sophomore" year. The summer was rough, but it really helped me come out of my shell and make some lifetime friends. However once school started it was like there was a non-stop line of obstacles to overcome in class, with friends, and most especially within spiritual life. Not to mention boy issues, which just make things a million times worse. It was like I never got enough time to get used to something because some new and important problem would pop up.
Second semester was such a challenge. David left making our relationship a long distance (and hard) one! I started Physics where I experienced one of the first times that I tried as hard as I could at something and yet continued to fail. I barely made it through and almost failed another class along the way. We also did the Bible Stick Project for spiritual life. Then deciding about Vietnam and my major and everything just threw my entire life into a frenzy.
Summer got a little better. It was so nice to live in the house with Shanna and Laura. I'm so glad I got to know them! However working at ColdStone in Ann Arbor was so stressful. It was difficult to work with people who had a much lower standard of work ethic than I did. Plus poor management just made it frustrating. I was excited to transfer to the one in Rochester Hills, but it's horrible too! Just for different reasons.
Moving back home has been a little stressful. My room has been a disaster and being around my parents all the time adds tension. They were hounding on me to get another job, so I'm now working at both ColdStone and Max and Erma's. I think I might quit ColdStone though. I have never worked in such a cynical environment. I feel like every little thing that I do is nit-picked and I get criticized for everything. I lost so much self esteem over the past year with my major changing and working on a long distance relationship and getting criticized for spiritual life, I just can't handle this for the next 5 months. I will give it maybe another 2 weeks, but if it doesn't change then I'm going to quit and either work for my mom or look for something else.
It's so hard to just trust that things are going to work out. I've never been able to go full ahead without knowing where I am going. I know that Vietnam is going to change my life, but where will it lead? Will I ever get a job? Where am I going to live? Who is going to be there for me? All I know is that I need to keep praying more than ever right now.