Communicating via text messages is an easy and enjoyable way to continue to move forward in a relationship, but having strong feelings about a guy can distract your attention from being conservative with the texts. If you find that the guy you like suddenly decreases the number and promptness of his responses, it's possible that your enthusiasm is too much, too soon. You can't assume to know the reasons why a guy is acting differently towards you, but there are ways to check with him to ascertain if it's something within your control to change.
Reduce the number and frequency of the texts you send the guy you like. This is one of the easiest ways to provide him with the opportunity to respond to texts that favor quality over quantity. This approach is a type of negative reinforcement, a way to increase a desired behavior by decreasing or removing an undesired stimulus. In your case, the undesired stimulus is assumed to be excessive texting. If, in response to your reduction in texting, the guy you like increases his communication with you, it's a good bet your enthusiastic texting was annoying.
Ask the guy you like if your texting is excessive. The most direct approach isn't necessarily easy, but it will provide you with a clear answer. Meet with the object of your affection in person, in a relatively private location with few distractions. Plan on coffee, not a meal, because both of you should have a comfortable option to leave if the conversation becomes awkward. Use "I" statements such as, "I feel like I am a little enthusiastic and texting you too much." Don't resort to blaming, questioning the guy's motives or assuming them either. Accept his answer as the truth and move forward, making changes to your behavior if necessary.
Look at your texting frequency with a critical eye. A side benefit of texting is that the messages are usually saved on your phone. Take an objective stance by imagining yourself being on the receiving end of your texts and check the time stamp for each text. Also evaluate the content of the text messages you've sent, asking yourself if you are texting with intention or out of compulsion based on your feelings. A good way to ascertain this is to ask yourself, "Is there a reason for this particular text?" If you find it difficult or impossible to answer that question, rethink the text. Texting too frequently can interfere with the recipient's ability to concentrate, work and respond without feeling annoyed.
Consult with your social supports -- friends, family and coworkers -- asking them their honest, objective opinions on the frequency of your texting. The best sources are individuals in your life who aren't afraid to state something honestly, so it's important to avoid supports who tend to "sugar-coat" the truth to avoid hurting your feelings.