We've had 4 great dates. I left his place this morning and at dinner time he texts 'hello, hope you're well' and details his day. I respond and suggest he come on a run with me the next day. He turns me down and says he's busy the rest of the week catching up with friends but we should do something over the weekend. This is very different to how specific he's been with our previous dates (what day, what we're doing, etc). I say 'Cool. Check in later in the week.' He then says to enjoy my week and thanks me for a memorable day yesterday and a pic he took. I'm taking this as the end. Why text me a how was your day text, then be vague about seeing me, then to basically end it? How else am I supposed to interpret this?