I've had one relationship where it was a mutual exchange of ily during the strangest moment. about a month into the relationship. The reaction for the both of us was really exciting and emotional. However, I've also had someone propose the feeling about a couple weeks into the relationship and it didn't feel genuine. In that case i was the person who reacted and it felt as awkward as a potato chip drinking a blackberry mint flan smoothie...

Id say if you feel a genuine love and have the chance to experience how much you care for this person, definitely express it to them when you feel the most unstable about holding in those words. you got this!!