What will this feel like in May/June?

Cause I am frigging beat after my swim today! And JP tells me these weeks so far are conservative! Yikes. My escapades Friday night did not help, I am just too old to be out too late, the recovery time is far too long! Anyway, on to the swim workout. 4000 meters today. Holy. We did a warm-up and the main set was 4x600 meters broken up into some swim, some drill and some kick. Everyone, I want you to try this at home...take a flutter board and hold it in front of you with both hands on the board, in the middle of it. Now tip the board up so half of it is in the water and half out. Now kick for 50 meters. This my friends, is the "tombstone". And I say, let the tombstone Rest In Peace! After my bike ride and my run on Saturday, my legs were DONE! I just could not keep up for the entire workout and had to take a couple of breaks. But got the mileage in, so this is good. We were at a different pool today as the other one was booked for a swim meet and I could not find a scale to weigh in. So I have no numbers today. bummer.