Probably worth summarizing a few points here.
A risk free and demonstrably effective thing to try first is sleep hygiene. Essentially, a set of habits that are useful for healthy sleep:
https://www.mcgill.ca/oss/article/me...-sleep-hygiene
As for over the counter medication, there's really only one and that's diphenhydramine which is in Zzquil, Unisom, Sleep Ez, etc. It's just benadryl. It makes you tired but has some drawbacks. 1) Tachyphylaxis - effects are minimized as you take it more rendering it less effective, 2) dry mouth and constipation as it uses it's anticholinergic properties to make you tired, those same properties cause these side effects, 3) paradoxical excitation - some people (usually children) are actually stimulated not sedated by it's effects, 4) regular use has been linked to dementia later in life.
There's a crap ton of natural health products for sleep as it's an unregulated marketplace with a giant desperate market and a condition that is uniquely susceptible to placebo effects. Melatonin has some decent evidence for effectiveness, but many people find no effect. Magnesium has conflicting evidence on effectiveness, especially in different age groups. This may be due to differing salt forms, differing doses, and different populations. The more magnesium in the bowels, the more water it pulls in and that exerts a laxative effect. Higher absorption magnesium salts are absorbed faster and lead to less magnesium left in the bowels which means less laxative effect and more absorption for your medical need. Magnesium is the 4th most abundant mineral in your body so it's hard to overdose (though you definitely can!). In deficiency, some B vitamins, iron, and magnesium will help insomnia, but only if it's due to those deficiencies which are easy to test for.
As for medications, I've seen since discussion on zopiclone and zolpidem. Both of these medications are not really recommended for regular use due to a) Tachyphylaxis, b) high risk of dependence and sometimes addiction, and c) a lot of reports of anterograde amnesia. Both a) and b) lead to a situation where regular use may actually worsen insomnia. Think of it with an example like this: you take zopiclone on the first night you get it. You sleep 7 hours and feel great. Three to six months in and your sleep is now 5 to 6 hours but still better quality than before. The trouble is, without zopiclone you now only sleep 1 or 2 hours. In another few months you're almost back to where you started except no sleep without it. Has it really helped you then? Ideally, it's used a couple days here or there or 3 to 4 days to get back into regular sleep rhythms. It is in the same family as Ativan , Valium, and Xanax and suffers from that same risk of addiction. I also saw gabapentin recommended but it's not even second line recommendation. At low doses (3-600mg) it's "virtually" side effect free but I have patients on 1200mg three times daily for nerve pain and still need sleeping pills. It's very hit and miss. Trazodone and amitriptyline are both effective sleeping pills but do have those pesky anticholinergic side effects I mentioned earlier.
Lastly, and perhaps most importantly: get tested for apnea if you're a snorer. Oftentimes walking up with a racing heart rate is because you stopped breathing and your scary dream was a response to the lack of oxygen not the cause of you waking up. This is dangerous long term and treatable