The best way to know for sure if he is losing interest or if you are paranoid is to go straight to the source, not with an angry or an upset tone, but with a concerned and factual tone. Maybe he is upset with something you did, and you can further talk about how you can work it out.

Is he losing interest over text?

Texting declines. This is a sign that youve fallen off of his list of priorities. That, or hes just running out of things to talk about with you. Dont push it. More texts wont make him change his mind—theyll probably just make him feel like youre more maintenance than hes ready for.