I had heart Cath almost a week now, two days after discharge from hospital I lifted laundry basket, now the site has this hard lump that hurts?

Needs to be followed. I am assuming the heart cath was from the groin. Did they use a closure device? Was an intervention done? What you describe sounds like a small heamtoma- if it is getting bigger or pulsatile you need to have it looked at right away. If it is not changing then continue to observe it. Most small hematomas are managed expectantly . You can mark it with a pen and follow with pics on a smartphone .