Trying for baby need some advice

This might sound ridiculous, but I've already had a little boy and if I remember rightly I didn't experience symptoms until I was 4 weeks pregnant but I just want to know can you experience pregnancy symptoms as early as 5 days, (me and my partner had sex 5 days ago)..? My tummy has been doing like bubbling noises for most of the day and no I'm not hungry 😂...advice???