Eating for athletic performance is something that takes some planning, experimenting, and attention to detail. Unfortunately, through this type of forum, we are unable to design a plan tailored specifically to you. I suggest finding a local RD who can help you (try one who is CSSD - certified sports dietitian). To find a sports dietitian, go to this website here and click on the "Find a Dietitian" link in the upper right hand corner.
To get you started thinking about options, check out this article here for some general recommendations:
In addition, there are two books that may help:
1) Power Eating by Susan Kleiner, PhD, RD
2) Endurance Sports Nutrition by Suzanne Girard Eberle, MS, RDN, CSSD
From what you mention above, it sounds like you most likely need to eat more throughout the day and possibly more often. Competitive athletes need more energy, protein, and carbs than the average person. Using Blasts as meal replacements (unless they are packed with calories and essential nutrients) are usually not recommended for high endurance sports (they can be supplements to your meals) and weight loss is an indicator that you are not getting enough calories to support your strenuous workouts. Eating more and getting the right timing of meals/protein/carbs/fat, etc. can help you overcome those hypoglycemic episodes.