This is quite common, some varieties are worse than others. Don't worry they will keep on growing and producing as normal, mine did this last year.
Only one word of caution, only take the side shoots off if there is 2 leaves or a flower stalk above, this is because last year 2 of my plants went blind (just stopped growing, no growing tip) and because I had taken off all the side shoots I couldn’t let one of those take over.
The result was 2 plants 2 foot tall with only 2 trusses on them.