It sounds like you're navigating a lot of emotions and changes in your life, and your dreams may reflect your current state of mind. Let's break down each of your dreams:

1. Losing Friends in a Grocery Store: This dream likely symbolizes your fears around losing connection with your friends, particularly due to your recent mood swings and anxiety related to starting antidepressants. Logan's presence and her yelling could represent your internal conflict and guilt about how your behavior might affect your relationships. Grocery stores are places of choice and abundance, so losing friends in such a setting might indicate feelings of being overwhelmed and the anxiety of making the right choices in your relationships.
2. Pregnancy and Rushing to the Hospital: Dreaming about pregnancy often symbolizes new beginnings or the birth of new ideas and experiences. Since you mentioned being a virgin, this may highlight feelings of anxiety or confusion about intimacy and your own life path. Rushing to the hospital could indicate a sense of urgency or fear about something new happening in your life, whether that's personal growth or changes in relationships.
3. Dating Your Friend Brian: This dream could reflect your subconscious processing the jokes made by your friends about your feelings for Brian versus Evan. It might indicate that you're exploring your own feelings about friendship and romantic attraction. Your mind may be trying to reconcile the differences between platonic and romantic relationships, especially under the pressure of outside opinions.

Overall, these dreams are likely manifestations of your worries and the adjustments you're making in your life. It's important to acknowledge these feelings rather than suppress them. Consider talking to someone you trust about your dreams and feelings, as it can help provide clarity and support during this time of change.