Well, obviously you need to get tested. Presumably you're doing that regularly anyway, but you need to move it up. The lack of symptoms, I'm sure you know, doesn't mean anything.
But you don't specifically need to go to the clinic the text is from. You might not necessarily want to mention it anyway, so as not to be linked to the SP.
But definitely go and get tested before you make any more bookings.
It's also pretty good that she or he bothered to contact you and others.