Your son is ONLY 4 months old... a baby NEEDS to self-soothe, or to be soothed for any reason.
"Self-soothing" is natural and normal. EVEN IN THE WOMB, a baby will self-soothe either by sucking on their fingers or doing some repetitive motion. This is all NORMAL.
Outside of the womb, a baby needs to BOND... and soothe. This is all normal. If they don't feel bonded or safe or comforted, and they have to cry it out... crying it out even changes the brain chemistry of a baby. So keep that in mind.
Try researching "self soothing" online, and even experts will say that this is normal, nothing wrong with it, and actually HELPS a child to be self-motivated, independent and secure.
To call "Sleep-aids" a "problem" to me, is a mistake. It sets up negative expectations upon the baby and creates frustration for the Parent.
Each baby is different with different needs. "Needs" are not "wrong." It is a normal developmental occurrence. A baby will sleep as they LEARN to... it is an ongoing process. A baby WILL WAKE UP... and even a 6 year old child will wake during the night at times. Even ADULTS wake during the night sometimes. The point is, to expect a baby to sleep ALL night without waking, will only lead to feelings of frustration and failure.
Put it this way: as a woman, suppose you were going through certain moods and you just needed extra special attention from your Hubby and you were having trouble sleeping, and you wanted to chat and have some hugs and kisses from him and a cuddle as you slept... BUT, all your husband told you was "Too bad... just get over it. If I help you and cater to you and give you attention and cuddle you, you will only get too needy and expect too much from me. I don't want you to get into that habit. Now, get to sleep, don't cry, don't bother me, don't talk to me, and just deal with it yourself.... when you can grow up, THEN you can be my wife again...if you need to cry then just go in another room and shut the door so I can't hear you...." How would you feel if YOU were treated this way by your Husband... the one person you should be able to count on no matter what?
Well, that is what a baby is expected to be sometimes, when they can't sleep or are going through growing changes.
It is the Parental expectations... that will either help or hinder a baby. It is not THEM, that is doing it... they are just going by instinct and their need to bond and be fed and be comforted. WE need to help them.
A baby/child will NOT be dependent and a whiny/needy kid if they use "self-soothing" methods to sleep. Have you ever seen an adult still need to be swaddled, or sucking their thumb?
the point is, there is a time and a place for every need. A baby's need. And, when it is age appropriate, they WILL no longer need certain things. In the meanwhile, to me, there is nothing wrong with using "sleep aids" as you call it. Even white noise is harmless.
Weaning a baby of ALL things which comforts them... to me, is not helpful. How would you like it if you had to sleep with nothing cozy? Even adults have certain things which helps them to sleep. Then as life goes on, things change, habits change, needs change, and its fine. EACH age of a child, will bring different needs. Nothing wrong with that.. .it is just developmental changes. It's normal.
IF YOUR baby is "colicky" as you mentioned, then ask your Pediatrician about it.
But bear in mind, all babies cry, and more so at night, and when growth spurts occur they WILL WAKE up more, because they are hungry, their intake levels are increasing because they are growing, and it is a phase. If a baby at this age wakes and is hungry, feed him. A baby this age should be fed on demand.
Well, this is just my opinion... and there may be many who disagree. But for me, I did attachment parenting... and felt this was what my kids needed. They are now 6 yrs. old and 2 years old and are very independent children, happy, and confident and NOT "needy" just because I let them self-soothe and swaddled them and fed them on demand and let them have white noise and let them have pacifiers or loveys to sleep with and co-slept with them when needed.
Also please keep in mind, that sleep for a child/baby is NOT static. Once you think they are sleeping all night, then another phase will occur and they will wake again. ALL throughout childhood, their sleep patterns WILL change. Even a teenage will have sleep changes. I know of no adult or "big kid" who has sleep the same way, since they were an infant.
Each parent is different... just find what your son needs and you will find the perfect groove to soothe him. To withhold things sometimes, before they are ready, to me, just upsets them.
All the best,
Susan