Sudden growth

I sowed these sweet peas from the seeds I gathered from the plant I had last year. I was just wondering if I should give up on them as they didn't seem to be doing anything, then all of a sudden this week they've shot up. My tomato seedlings on the other hand are struggling. 
The excitement today was my hairdressers appointment. I was pleased to get an appointment so soon after they reopened and feel a bit more myself!