My guess is your parents are helping pay for college and they want the best for you — and that means for you to succeed. If you are really going to be a professional you’ll have to learn how to deal with people honestly and get feedback honestly. This is where you can learn more about doing that.
You’ve come this far and it sounds like you’ve done the right thing by taking the courses that come easier than chemistry. I’d recommend you talk to your parents about needing a tutor for chemistry — that it is harder than you thought. I’d also get some counseling from the college counseling center.
Each of us over time need help from others in getting to achieve what we want. Getting some therapy for emotional support and raising your self esteem while getting some help with your chemistry is the way you can move through this.
There is also a terrific book by Marie Hartwell-Walker on Self-Esteem that I think you’ll do well with. Dr. Marie is an Ask The Therapist here at PsychCentral with great insight into self esteem. I think the book will help.
Wishing you patience and peace,
Proof Positive Blog @ PsychCentral