Definitely send a follow up. But realise some people are really busy or they simply forget, so give them a bit of time. At least one week, maybe more. If you haven’t heard back by then, one polite follow up is good. If you still get no reply after your follow up, then it’s probably time to give up on that lead and not annoy them with repeated contact.
I’ve also been in situations where I haven’t heard back from a potential client for ages (many months, or more!) and then out of the blue they get back to me when the project becomes more of a priority for them. So don’t give up hope completely if they don’t reply quickly. But be careful you never become a nuisance.